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Mike6

Engine running problems

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Car has been running roughly for years and even after an engine rebuild I still didnt get much of an improvement. A couple of months ago I was going to a meet at Newlands corner and the car started to judder, misfire then backfired a few times and died. I called out the breakdown people who arrived after about an hour, by which time the car had cooled down and started first turn of the key. They followed me a short way but the car got me home ok. I decided it must be fuel pump related (original pump) and replaced this plus all fuel lines and the filter.

 

Car ran ok on a few local drives so last Sunday drove back to the Newlands meet and go about as far as last time when she lost power, coughed and spluttered but I limped to Newlands. A few theories were suggested like vacuum lines, distributor etc. I started back home and having cooled down it didnt run too bad at first but within a few miles the symptoms returned and the car cut out completely. She restarted, ran really roughly and then cut out altogether. This time I did come home on a low loader.

 

Tried restarting at home but no luck. I have stripped out the distributor but everything seems ok, and no sign of any obvious electrical problems. All the obvious things were replaced last year so decided to invest in a fuel pressure meter which suggested hardly any fuel pressure going through to the carbs. I adjusted the regulator to the 4 psi spec and the car has fired up first turn of the ignition.

 

However slightly concerned about using the car as dont want to break down again with the same symptoms (might not be covered for breakdown). So does it seem likely that I have discovered the cause of the problem or is low fuel pressure unlikely to be the cause of breakdown.

 

Any ideas please ??  

 

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What was the pressure before adjustment? With everything that's gone on, Mike, I'd suggest your engine would benefit from a comprehensive checkout.

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I'd say the pressure was showing about 2 psi but couldnt check with the engine running as it wouldnt start so just took it with ignition on. A fair few turns of the adjuster was required so just to be certain have ordered a new regulator and have sent off for a meter with a smaller scale to get a more accurate reading. I will then recheck pressure with engine running when new regulator arrives.

 

A comprehensive checkout is probably a good idea. Keep promising myself one but then something else fails. About the only thing not changed is the amplifier (AB14)  and these are obsolete but managed to get one from a Jag breakers.

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If you're not covered for breakdown I'd suggest taking it for a run but doing a fairly circular run not more than a couple of miles from home and keep going. If it does break down you can then arrange a local man& trailer type firm to transport it home for a lot less than a breakdown firm would charge for recovery & transportation 50-100 miles.

 

My gold Excel had a misfire when warm and I'd tried mixture etc, no avail. It mucked my about during the MOT until it finally failed and wouldn't start on the way home from the MOT station. cause- AB14 breaking down when hot.

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Hi not sure if its the same but on my 1987 Excel I had similar problems, missing wont start, etc, changed everything including AB14 , it turned to be the pick up in the distributor, as the vacuum was applied the wire from the pick inside the distributor up to the outside of the distributor stretches and the inner wire broke down, I remember testing the wire and I one position no current would flow, hard to,detect though

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At the moment I am going on the low fuel pressure problem since the car started instantly when I upped the pressure to 4 psi. I just wanted to know if the symptoms I was experiencing could be down to low fuel pressure (about 2psi) at the carbs.

 

I have breakdown cover but it seems unless the fault has been fixed you cannot expect a subsequent tow  

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That doesn't make sense.

 

Most breakdown companies exclude the 2nd recovery for the same problem within a period of time.

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At the moment I am going on the low fuel pressure problem since the car started instantly when I upped the pressure to 4 psi. I just wanted to know if the symptoms I was experiencing could be down to low fuel pressure (about 2psi) at the carbs.

 

The fuel pressure is only relevant when the turbo is boosting, at tick over & off boost driving the pump only has to trickle the fuel into the carb float chamber until the floats rise & close the needle valve. It works on the same principle as your toilet cistern.

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John. Blast that means I have just wasted my money. However, there could be a fault with the regulator to give such a low pressure (probably about half that required) and whilst I acknowledge what you are saying I would have thought that with very low pressure on a hot engine it must have some effect in weakening the mixture to such an extent that very erratic running or stalling would result.

I should have the new meter in the morning so I will set the pressure back as before and see if the car starts ok. If it does then I guess I am looking elsewhere for the fault.

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Did you set the float heights and what did you set them at? I find it can make quite a difference although I don't think that is your main problem. As Jon says low pressure won't make any real difference at idle or regular driving as long as there is enough flow to keep the float bowls topped up.

Trevor.

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Well more accurate meter arrived today and petrol pressure was fine so that discounts that one as others have suggested. Spoke with Steve at SJs to see if I could cancel order for new Governor but too  late so thats £100 wasted. He talked me through the problem and said it would most definitley be the electronic pick up inside the distributor or the engine overspeed limiter.

 

You can run the car without the overspeed limiter connected so have disconnected it and now await delivery of the electronic distributor pick up. He didnt reckon the AB14 would be at fault although Andy Clements says this resolved his problem. I have a second hand one somewhere so if the other items dont resolve the issue will try that.

 

Will post up the results.

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You should definitely go with what Trev said first - setting float levels made a big difference to his.  Make sure all the easy/inexpensive stuff is OK first!

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Well more accurate meter arrived today and petrol pressure was fine so that discounts that one as others have suggested. Spoke with Steve at SJs to see if I could cancel order for new Governor but too  late so thats £100 wasted. He talked me through the problem and said it would most definitley be the electronic pick up inside the distributor or the engine overspeed limiter.

 

You can run the car without the overspeed limiter connected so have disconnected it and now await delivery of the electronic distributor pick up. He didnt reckon the AB14 would be at fault although Andy Clements says this resolved his problem. I have a second hand one somewhere so if the other items dont resolve the issue will try that.

 

Will post up the results.

Why can you not cancel? Distance selling regs should allow that if not yet sent, assuming it's not especially made / customised.

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Easy check of pick up by checking ohms (exact figure in book) - They only go bad on cars with a vac advance as the wires break through fatigue - new 'tails' can be resoldered.   I would also check you have correct coil, such as dlb198.   Have you done a simple check of fuel volume to make sure you could, say, quickly fill a'jamjar' ?  Finally, what do your plugs look like - If its cutting out through fuel starvation they are likely to be dry and smell 'scorched', if cutting out through elrctrics, likely to be wet with fuel. 

NB - not wanting to rub your nose in it, but there is a new fuel regulator on ebay for £35....

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Thanksfor comments. I will check float levels but cannot think that would be the cause of sudden breakdowns.

I have sent an email to SJs but they said they have had to order unit in.

I am not that confident with car electrics but as it is breaking down when hot - car started easily this morning, it presumably has to be an electronic unit breaking down under load. I believe it is not just the wires that can go but the pick up unit itself can fail. The plug were definetly damp when I took them out and when I removed the plenum to get at the distributor there was a fairly strong smell of petrol so hopefully this points again to the electrics.

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Check the balance pipes that run between the Carby's.  I had a problem similar to yours and eventually found the banjo fittings were a bit loose and were leaking air. It took me a few days to find it and only 5 minutes to fix once i had.

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Hi Mike,

 

I've had exactly the same problem this last week - popped, spluttered & died (on a fast uphill). Couldn't restart, then kicked over first time with RAC man (we had moved on to level ground by then).

 

Next day, same problem, same place. Helped diagnose a bit i.e. something loose that disconnects on  steep hills.

 

If you're backfiring, it is unlikely to be a fuel issue - fuel is making it through to the exhaust to pop away (mine was VERY impressive).

 

Steve is on the right lines, but I traced my problem back to the ignition switch (after replacing every connector & soldering all weak points). Intermittent faults are very hard to diagnose on the amplifier / limiter modules IMO.

 

Just a final thought - do you have optronic ignition - 3 wires coming out of the distributor? If so, it's worth taking the distributor cap off and cleaning the IR sender & sensor (straddling the maltese cross thing) with alcohol & cotton bud. Mine was covered in black dust & solved this issue 2 years ago.

 

Good luck & don't feel too bad about the pressure governor - if it's the one with a switch (wire connected), it can cause erratic problems.

 

Good luck, it's just such a shame these things pop up now we've got lots of sticky tarmac to play on!

 

LA

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Not balance pipes, they are tight. Distributor has two wires coming out. The new distributor pick up arrived on Friday but as the car is in the naughty garage and the weather is so good decided to let it sit in their and sulk (car not me). Met a mechanic at a party on Saturday and he thought the distributor pick up as well. It seems they can fail even with cables looking fine so will fit it this week and see how it runs, also with rev limiter disconnected.

 

Thanks for comments, all gratefully received.

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Well after leaving the car for a couple of weeks to sulk in the garage I have fitted the new pick up in the distributor (after dismantling half the car for easy access) and noticed that the cable running from the pick up to the ignition amplifier (AB14) was rock hard and was starting to chaff through where it was rubbing out of sight. So purchased a new one of these but immediately ran into problems with different connectors (even though SJs assured me they just pushed together). After sorting this decided to fit the new fuel governor and adjust the pressure and disconnected the overspeed limiter.

 

Then, charged the battery and took the car for a long run today driving in circles of about 5 miles just in case the car broke down again. And what a difference, cannot remember the car ever going this well. The jerkiness in first gear was gone, just a smooth pull away, the popping and banging on overun was still there but much more subdued. At 3000rpm the turbo boost cut in and she just wanted to surge ahead in 4th. Unfortunately the congested roads, stupid speed limits and massive craters (sorry potholes) meant I had to hold back.

 

Now I finally know what Esprit ownership is all about - all down to the pick up and a length of hardened cable. I have a big smile on my face tonight! 

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