K series running issues / possible misfire?

[Guest]

....and so the fun begins! Not even 3 weeks into 7 ownership and I have a starting/running issue with possible misfire. I've been reading a lot of the archives, some of which I have been able to relate to, but as is common with these kind of issues, diagnosis and remedy is often different from one car to the next.

 

My car is a 1.6K EU3 and competed in the mega-grad series. The engine underwent a rebuild by McMillan, and having had a chat with them, the engine would have been upgraded to produce circa 140bhp comprising the Supersport upgrade (cams, ECU remap), ali VVC inlet, 52mm TB, solid lifters & forges pistons. Engine seals have remained in tact.

 

Symptoms:

1) The engine requires a lot of cranking before it fires, needs to turn over for 2-5secs before firing. 50% of the time it'll fire up ok, 30% it'll start but almost conk out before regaining idle, and occasionally it wont start and will need a little bit of throttle to get going but then idles fine. This happens when engine hot or cold. This happened from when I bought it but was told it was probably due to having 95RON fuel in it. I have run it on Tesco 99RON ever since but it hasn't helped.

2) The car is extremely difficult to drive smoothly before getting up to decent temp, particularly noticeable in 2nd/2rd gear getting to the end of my close. Very bunnyhoppy and almost need to ride the clutch slightly to drive smoothly. Once down the road and warm not so much of a problem. Again, happened from when I got the car, assumed it was part of the character and a case of TADTS, but now other symptoms have cropped up I'm guessing the severity of the un-drivability is probably linked.

 

The remaining symptoms I've noticed, and have got worse, in the last 100 miles or so and are in order of when I first noticed them...

3) When I'm running at mid revs in say 3rd gear and I go to slow down, as I dip the clutch to change down a gear I get little pop (deep tone, low volume) from the exhaust just as the revs start to drop. At first only noticed when engine cold, but seems to have got more frequent, and to a lesser extent when warm too. Sign of a misfire?

4) When idling (and also at higher revs while stationary), if I give it a sharp blip of the throttle, it will hesitate for a split second before then revving up fine a freely. Sounds a bit like a "brum.....brooooOOOOOOMMMM!". However, if I blip the throttle progressively it will rev up smoothly - "broooooOOOOOOOOOOMMMM!" 😬 Again, sign of a misfire?

5) When I perform the revving described above while out of the car and observing the exhaust, with a smooth progressive rev there is no smoke. With sharp revving inducing the hesitation, I see a puff of dark smoke (un-burnt fuel?). The quicker/sharper the rev, the more pronounced the hesitation and the bigger the puff of smoke. Misfire?

6) Over the last 100 miles or so I have noticed that the car has lost a bit of its punch above 4K rpm and it's now obvious it wasn't just my imagination. For the first time today on the way back from work I could feel it misfiring slightly if I put my foot down on the motorway in 5th gear ☹️

 

Idle seems quite lumpy and almost diesel engine like sound, but I've put that down to the cams and solid lifters more than related to this issue...?

 

So those are the symptoms, now here's is what I've tried after doing some archive reading:

- Removed the IACV and cleaned with carb cleaner.

- Tried resetting the TPS using the "switch ignition on/off several times" method

- Tried disconnecting the lambda and ran/revved the engine while stationary

All of the above has not made any difference.

 

Tonight I also inspected the spark plugs. First thing to note was the code on them is NGK PFR6N-11, however, I'm lead to believe the recommended plug on BC is the NGK BCPR7ES. I have 4 of these on order and should arrive early next week. Regarding the condition (Pics below), they generally looked OK and were fairly even in wear and colour, although plugs 1 and 4 were slightly more brown and plug 1 (far left) had a bit more deposit build up and the body of the plug was more grubby. All the plugs seemed to have oily threads too for some reason? Can the plugs be ruled out?

 

What to do/check now?

 

Apologies for the lengthy post but as you can tell I'm very new to sevens / k series and want the best chance at sorting this out Thanks in advance!!

 

http://i75.photobucket.com/albums/i315/pullpete/20140411_211232.jpg

http://i75.photobucket.com/albums/i315/pullpete/20140411_211438.jpg

http://i75.photobucket.com/albums/i315/pullpete/20140411_211513.jpg

 

 

Edited by - Smiffy7 on 11 Apr 2014 23:01:08

 

Edited by - Smiffy7 on 11 Apr 2014 23:16:15

[Jonathan Kay]

Great description. Lengthy is good.

 

1 Whom (roughly) did you buy it from? If it's a dealer or similar I'd suggest it goes back to them for diagnostics on the ignition and the valve timing.

 

2 When was the engine last running well, when was the rebuild done and what has been done to it recently?

 

3 This won't account for all the problems, but let's make sure you're getting lots of volts. What's the voltage before starting, when cranking and at idle? Does the cranking sound fast?

 

4 You might like to add where you are. There are some very helpful members around...

 

5 Don't despair: you'll get this sorted.

 

Jonathan

 

 

 

 

[Racingshoe]

It could be one of your sensors is faulty. Try unplugging the lead on the air temp sensor or coolant sensor (ECU one, not the gauge one) and see if the running improves.

[revilla]

Just a small point to relating to the previous suggestion - on most EU3 Ks the intake air temperature sensor is integrated into the manifold pressure sensor and if you unplug that the engine just quits.

[6speedmanual]

TPS reset is not ign on/of several times. It is ign on, 5 clean closed to open to closed throttle sweeps, ignition off.

 

Otherwise as above.

Check battery voltages and earths.

Check harness connections secure and not corroded.

"mostly" the sensors are fairly reliable.

Plugs - certainly worth putting in a new set as only £10.

 

Can you tell when driving if it's a regular misfire or general spluttery, hiccoughy runing?

 

Peter

[Titanium7]

Had a similar problem recently and it turned out to be the TPS plug was not properly seated onto the TPS.

 

Edited by - Titanium7 on 12 Apr 2014 08:25:42

[Guest]

Thanks for all the swift replies! A couple of other things have sprung to mind which could potentially be linked symptoms:

 

7) When switching off the engine it will continue to run for approx 2secs after turning the key. This has happened since buying the car but thought nothing of it.

8) Only noticed this once, about a week or so ago, but on this particular journey I waited until the engine was up to temp (80deg indicated). I then gave it a spirited blat through 2nd and 3rd and 30secs later the temp gauge read approx 50deg. The reading then gradually stabilised at 80deg.

 

Quoting Jonathan Kay: 

Great description. Lengthy is good.

 

1 Whom (roughly) did you buy it from? If it's a dealer or similar I'd suggest it goes back to them for diagnostics on the ignition and the valve timing.

 

2 When was the engine last running well, when was the rebuild done and what has been done to it recently?

 

3 This won't account for all the problems, but let's make sure you're getting lots of volts. What's the voltage before starting, when cranking and at idle? Does the cranking sound fast?

 

4 You might like to add where you are. There are some very helpful members around...

 

5 Don't despair: you'll get this sorted.

 

Jonathan

 

1. Private sale so no warranty

2. I would say it appeared to be running pretty sweet for the first week/500miles. I took this opportunity to have a thorough read through the history folder, which is pretty big! I wasn't able to find the paper work specifically relating the the mega-grad upgrade, however, I found a McMillan invoice from 2008 stating "mega head refresh". I think it was done in 07 or 08. It appears to have had a couple more "head refreshes" from 08-11 and raced in 1 or 2 seasons. The previous owner I bought it from then stripped it , chassis check/repair at Arch, re-paneled, re-sprayed and rebuilt with new gearbox in early 2012. Since then it has just been on the road and routinely maintained with the last service last August/1500 miles ago.

3. I will check the battery today and report back

4. I'm in south Hampshire

5. All part of the fun right? Just so long as I'm not doing this every few months....!

 

@Racingshoe/revilla - can you help me locate the various sensors please? I've had a quick search in the archives and Google but found nothing definitive. To test the sensor, do I unplug with the engine on or off? And is it simply a case of if I can't replicate the symptoms with it disconnected then that is the culprit?

 

Quoting 6speedmanual: 

TPS reset is not ign on/of several times. It is ign on, 5 clean closed to open to closed throttle sweeps, ignition off.

 

Otherwise as above.

Check battery voltages and earths.

Check harness connections secure and not corroded.

"mostly" the sensors are fairly reliable.

Plugs - certainly worth putting in a new set as only £10.

 

Can you tell when driving if it's a regular misfire or general spluttery, hiccoughy runing?

 

I am lead to believe the TPS reset procedure you mention above is for the EU2 engine and the one described in my OP is for the EU3. I did try both though and neither made any difference.

Is there a "best practice" to cleaning/making good harness connections, any particular cleaner to use?

Doesn't seem to be a regular misfire, only noticeable doing things exactly as I describe in my OP.

 

Am I right in thinking the TPS is located within the black throttle cable mechanism on the side of the TB?

 

Off out to the garage now - wish me luck!!

 

Edited by - Smiffy7 on 12 Apr 2014 11:24:56

[Jonathan Kay]

Thanks for the additional information.

 

1 Ignore the running on for the time being. Might just be the back EMF from the radiator fan.

 

2 Voltages as above.

 

3 Electrical connections: you can just look and wiggle, or you can break, inspect, clean (cloth and fluid up to light abrasion) and reassemble.

 

4 I don't know my way around all all the sensors or a logical way to test them...

 

Good luck

 

Jonathan

[Roger Ford]

NGK PFR6N-11 are correct spark plugs. These or Rover NLP100290 are mandated for Super- and Mega-graduate cars. BCPR7ES might be OK as well but the ones you have in there are not incorrect.

 

Have you washed it recently? In particular, have you jet-washed it around the engine area? Your symptoms sounds consistent with corroded HT leads, which can happen when water gets into the plug recesses and sits there for a while.

 

Two of the HT lead contacts can be cleaned up (I think the ones which don't have the coils on), the other two are much more difficult. You could buy a secondhand set off ebay (these look correct, but you should check) or you can probably even get new ones on ebay for not too much money.

[Roger Ford]

Quoting Roger Ford: 

NGK PFR6N-11 are correct spark plugs. These or Rover NLP100290 are mandated for Super- and Mega-graduate cars. BCPR7ES might be OK as well but the ones you have in there are not incorrect.

 

Have you washed it recently? In particular, have you jet-washed it around the engine area? Your symptoms sounds consistent with corroded HT leads, which can happen when water gets into the plug recesses and sits there for a while.

 

Two of the HT lead contacts can be cleaned up (I think the ones which don't have the coils on), the other two are much more difficult. You could buy a secondhand set off ebay (these look correct, but you should check) or you can probably even get new ones on ebay for not too much money.

 

Edit: I've got a spare set of coils and leads if you want to borrow them to see if it makes any difference. If you're anywhere near Twickenham you're welcome to pop round. Happy to help fit them on the spot.

[6speedmanual]

Another way to clean contacts is with a soft brass wire brush. Make sure all switched off(!) And no whiskers falling off brush.

Reassemble with electrical waterproofing silicone grease.

 

P

[Guest]

Reasonably productive few hours on the 7 today. The bad news is it's still running poor & misfiring. Here's a run down of everything done so far:

 

- Removed the IACV and cleaned with carb cleaner.

- Tried resetting the TPS using the "switch ignition on/off several times" method

- Tried disconnecting the lambda

- Cleaned up the spark plugs, HT leads and coils (one of the leads a tiny spot of wear and also tiny slit, like a razor nick)

- Went round the entire engine bay and checked every harness connection I could find by pulling it apart (where possible), checking for corrosion, clean, fit, wiggle.

- Measured the battery voltage and got 12.8 off, 12.6 ignition on, 10.5 turning over, 14.3 idle.

- Checked the earth. It looked fine and has a date on it so assume it's 2 years old

 

All of the above didn't seem to make any difference and symptoms 4 & 5 in my OP very much apparent. In fact, when idling for the first minute when cold it is now apparent that there is a bit of misfire. Might have passed this up previously as being lumpy cams. Seems to smooth out as it warms up though.

 

I used my noggin and located what I thought were the sensors, coolant sensor being on the metal pipe over the exhaust manifold - removing this didn't make any difference. Also there is a sensor on the top of the radiator so I tried disconnected that too but made no difference. The air temp sensor was less obvious but I assumed it to be the plug connected to the TPS? I could be wrong But something interesting happened when I disconnected this - the revs rose and settled at about 2K rpm, but when I tried a sharp blip to induce symptoms 4 & 5, although it wasn't hesitation free, it was much improved!

 

@Roger Ford - I haven't jet washed it but I did give it a wash a few days after getting it. Pretty sure water must have gone through the bonnet.

 

So what would be next to do/check? I've got new plugs arriving next week, so I suppose new HT leads next? Would Redline be the best/cheapest place? What about new coils?

 

On the plus side I successfully topped up my coolant and fixed my horns! 😬

 

Cheers all!

[revilla]

If it is EU3 it will probably have a MEMS3 ECU (that looks like this under the bonnet, back of the engine bay near the battery). These are OBDII compliant and will allow a suitable scanner to read both DTC fault codes and "live data", displaying the current readings from the main sensors. You can get a suitable cheap and cheerful scanner that looks like it should do the job from eBay for £9.99 e.g. here. This plugs into the OBDII diagnostic socket, which you should find just dangling on the end of a bunch of wires somewhere near the driver's right knee, probably just tucked loosely behind the trim panel. Follow the instructions that come with it carefully. They do seem to be a bit temperamental at connecting sometimes, so keep trying if it reports unable to connect. If it asks you what type of vehicle you have, select any old Rover that has a MEMS3 like a Rover 400 or a Land Rover Freelander I as Caterham won't be on the list. This will give you all sorts of useful information to help you diagnose the problem. If you do get one and try it, it will probably come with a list of the meanings of the fault codes, you can look them up on the internet or alternatively post them back here and people will be able to tell you what they mean. Don't worry if there are a few, there are a bunch of "standard" ones that the ECU will often report and which you don't need to worry about. For example, it will probably have several codes moaning about the post-catalyst oxygen sensor not working (because the car the ECU came off did have one but the Caterham doesn't!). It may have some other codes which are more relevant to your problem. The live data will tell you if any of the main sensors or faulty, for example the manifold air temperature sensor which seems to be having some effect on the problem. My car was wired incorrectly when I got it (it appears a previous owner botched an engine upgrade) and the inlet air temperature was reporting -40C - basically because it just wasn't connected. With most of the sensors it is easy to see if they are reporting something sensible as they would have to be a long way out to give the symptoms you are seeing, so expect inlet air temperature to be about the outside temperature on the day give or take a bit and the coolant temperature to start off about the same and warm up to something arounf 90C when the fan is cutting in. I can't remember exactly what my manifold pressure sensor reads, but it gives ABSOLUTE pressure, so about 1013mb (one atmosphere) on an average day (basically about the same as a barometer, which is what it is) with the engine not running, dropping to something a LOT lower at idle as the engine is sucking frantically at the manifold against a closed throttle, then briefly rising if you blip the throttle. The throttle position sensor on mine reads about 3% with the throttle closed and should increase smoothly to 90-something% as you open the throttle (do it with the ignition on but the engine stopped so you can swing it slowly through the range and look for odd readings). Just look for anything that looks silly like water temperature 100C while the engine is still plainly cold, or a throttle position of 70% when it is clearly closed. Hope this is of some use, happy to help out if you want to post any results back here or BM me in case I miss them on here.

 

Edited to add that the ODBII scanner will probably have a feature to allow you to reset any error codes. It might be worth doing this as there may be all sorts of historical errors logged to confuse the issue, then take it for a drive and scan it again when you get back to see what new error codes have popped up again.

 

Edited by - revilla on 12 Apr 2014 21:44:35

[Guest]

@Revilla - thank you very much for your advice! I will definitely get one of those code scanners, seem like a great gadget to have in the garage, not only for this issue but for the future too.

 

Before I order one from eBay does anyone know of any shops where I might be able to pick one up today? I quick Google search was unsuccessful.

 

One thing I forgot to mention yesterday, I found something interesting when I removed the TPS for a clean (see pic below). On the inside, where the throttle spindle thing passes into the TPS, I found what looked like half a washer just sitting on the inner white plastic part where the spindle passes through. It looks a little odd because the washer looks bigger one end than the other - can anyone identify what it is, should it be there? I obviously didn't put it back in but should I be worried where the other half is??

 

http://i75.photobucket.com/albums/i315/pullpete/20140412_173732.jpg

 

Edited by - Smiffy7 on 13 Apr 2014 09:59:15

 

Edited by - Smiffy7 on 13 Apr 2014 10:01:21

[prangerman]

If the tps goes on and comes off the spindle with little force it's probably time for a new one. They are very sensitive to the slightest movement and if not a tight fit on the spindle it won't hold its position and setti g. Ask me how I know having cured a hesitation on my K series last year.

 

Peter

 

Edited by - prangerman on 13 Apr 2014 13:29:00

[halstock]

Smiffy, I had a running problem on my 1.6K that shared many of your symptoms and for which I sought advice here amongst POBC. As with many of these problems it could have been any one of a number of things and I had lots of "try this" advice which is really useful for ruling things out but ultimately you want if fixed so you can get out and drive it ! I went for periods believing it was lambda sensor related, then TPS, and other things, but when I ran out of the ability to follow instructions (not v technical myself) I had it taken back to Millwood where I bought it. They only had to listen to it running to say "coil packs" and having those replaced (I think there are two) solved it 100%.

 

Yours may well be something different but it sounds like ignition might be the right area to be poking around in. If you get chance to try new coil packs it might be worth a go.

 

Good luck

 

Andy

[evotell]

This is a great post and what are forum is all about. I have read with interest and learnt a bunch things. Question: is there a specific code reader needed or will an IPhone app do the same thing?

 

Edited by - evotell on 13 Apr 2014 14:03:05

[Jonathan Kay]

There are a few discussions about OBDII reading using apps on iPhones etc. I don't think they've ever reached the point of there being one that's tested and recommended.

 

If someone did find one it would be very popular.

 

Jonathan

[Guest]

Evening all. I hope you all had pleasant weekends blating round is the gorgeous weather - lucky sods!!

 

So my next plan of action I think, fit the new spark plugs I got coming this week, order one of those fault code scanners and see what that throws up.

 

Would the scanner identify any faults with either the HT leads or coils? If not, and if the scanner & spark plugs don't solve the mystery, I assume these would be the next logical thing check/replace?

 

Can anyone shed any light on the mystery washer looking thing I found in the TPS?

 

Thanks to all for the continued advice

 

Edited by - Smiffy7 on 13 Apr 2014 23:00:43

[revilla]

The OBDII fault reporting in MEMS3 was a bit primitive, so I'm not sure it will pick up on ignition HT faults. The easiest way to eliminate coil pack and HT lead problems is to swap them. There is a full set on eBay at the moment for £12 here. The picture only shows one set but the description clearly states "price for pair". So for £12 you get to replace the entire HT electrical setup, coil packs and leads together. I've bought enough parts to build a whole engine from eBay (literally) and never had a problem, and the chances of replacing one with another with the same fault are pretty remote. Ignore the fact that it says for 1.8, this will just be what they were removed from but I've double checked on Rimmer Bros and the part number is the same NEC000120 for all the non-VVC EU3 K-Series. If these ones have gone by the time you come to look at them, just search eBay for "k series coil packs", there are loads on there, just make sure you don't pick ones where the big rubber tips are red (obvious on a photograph) as these are longer ones for the VVC engine. They are trivially easy to swap over too. Ignition off, remove the three bolts holding the plastic plug cover in place, then remove two bolts from each coil pack and pull off. 10mm socket for everything. Refitting is the reverse, push them into place and replace the bolts. If I were you I would take a picture of the way the HT leads are laid out (they clip into grooves in the coil pack bodies) before dismantling to help make sure everything is in the right place when you put it back.

[Smithy77]

Revilla, thanks again. I think I'll buy a second hand set off eBay as you suggest. Presumably I can buy any set which says it's from a 1.6 or 1.8 k series, from any year or from any car? I've already had the old ones off to clean so I'm a bit of an expert

 

If a second hand set of lead and coils cures the problem, would you suggest investing in a set of new items?

 

- Measured the battery voltage and got 12.8 off, 12.6 ignition on, 10.5 turning over, 14.3 idle.

 

As no one has mentioned anything about my battery voltage readings above, presumably they are healthy?

 

Cheers

[Jonathan Kay]

Yes, those are fine.

 

Jonathan

[Smithy77]

Quoting Jonathan Kay: 

Yes, those are fine.

 

Jonathan

 

The battery voltage?

[Jonathan Kay]

Yes, the voltages are fine.

 

Jonathan

[revilla]

Yes, those are fine 😬

 

Anything for a 1.6 or 1.8 EU3 K Series, non-VVC.

 

EU2 had a completely different setup so you won't get the wrong ones. VVC has a deeper head so they are longer, but the big rubber on the end is red to make it clear so get black ones.

 

If you want to get new ones, parts numbered 4 and 6 here are what you want but to be honest if it were my car and the eBay ones worked and looked to be in good condition I'd probably just keep using them.

 

PS: Morning Jonathan