P38A Elastic Trickery problems.

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Pression de Gonflage

Pression de Gonflage

Well-Known Member
Posts
134
Location
Midi-Pyrénées region of France
Hello Folks and greetings to all my neglected chums.

'Tis said you only hear from people when they want something. Well.................er yes.

So after About 18 months of silence, I return to the fold and offer my cringing apologies to all.

I hang my head for having been out of touch, but I am now on the point of hanging the rest of me. The P38 has strangely been behaving itself. Until today. Got it out of the motor house this afternoon. Engine racing a bit, but I was not too concerned as it has often done that in the past, but usually clears after a bit.

Then I switched off, only to find that most of the warning lights were still on, along with all sorts of warning messages appearing faintly in the window. The baclighting was never great.

Disconnected battery and of course every light went out. Left it for about 5 mins, re-connected battery and switched on. The normal array of pretty lights appeared. Started the engine and all of the warning lights reappeared, along with various messages, including "Electrical Fault". Whatever the electrical fault is, as far as I can tell, everything electrical does actually work, window, lights, starter, etc;

So, to put it as succinctly as possible, HELP ! All ideas or suggestions will be greatfully received.
 
Last edited:
Datatek said:
Wet carpets and /or underlay in the right hand side footwell causing condensation in the BECM is one possibility.
Click to expand...
Thank you for the additional possibility. I will have a better look in daylight tomorrow. I have never tinkered with the BECM - is it sufficiently sealed to avoid damp getting inside it ? If Not I suppose I should expect the worst.

I should have l mentioned that the car is kept in a dry but ventilated garage.
 
Pression de Gonflage said:
Thank you for the additional possibility. I will have a better look in daylight tomorrow. I have never tinkered with the BECM - is it sufficiently sealed to avoid damp getting inside it ? If Not I suppose I should expect the worst.

I should have l mentioned that the car is kept in a dry but ventilated garage.
Click to expand...
The BECM is not sealed and does suffer with damp problems. Being inside does not stop leaking heater O rings causing wet carpet and BECM problems. If it has got damp inside, taking the lid off and drying it in a warm airing cupboard plus cleaning off any corrosion will revive it. The BECM is actually quite robust, the failures that do occur are often caused by external problems. It also gets blamed for many problems for which it is not responsible such as the fairly common fuse box failures.
 
A VERY GOOD MORNING TO ALL and particular thanks to Marjon, Grrrrr and Datatek.

Sorry for raising my voice, but it seemed appropriate because the problem seems to have gone away.

I did not do anything much last night but, I left the car outside overnight. The weather here is dry but very windy at present and if damp was the cause then I would like to think that the wind may have helped. I could not find any damp in the footwells or around the BECM, but who's to say that there was not some damp somewhere else ?

The car has not had a lot of use over recent weeks and no serious hard work, so it is being taken out for a gallop today. This often seems to clear the cobwebs, mine and the car's. This may clear the next ailment, that of over-fast idling (1200 to 1600) when it first wakes up. "I'll be back. Hasta la vista, Baby"
 
Good news. Make sure you have the aircon on (if fitted) as this will dry out the interior. In fact the aircon should always be on to protect the electronics from damp.
Lack of use is often a cause of problems.
 
Datatek said:
Good news. Make sure you have the aircon on (if fitted) as this will dry out the interior. In fact the aircon should always be on to protect the electronics from damp.
Lack of use is often a cause of problems.
Click to expand...

Good point.

Although I learned long ago about keeping the a/c always on, as it keeps it's "tubes" in good order and helps prevent windows misting up condensation in the winter, I had not considered the effect of condensation in hidden and important little places.

Thank you for that.
 
The aircon cuts off at outside temperatures below 4or 5 degrees:rolleyes:,,id check earth points and alternator output ,because engines sometimes rev ..idle slightly higher when theres no alternator load on it ,and as wee all know low power causes all manner of faults when theres nout wrong ;)
 
dubbleRR said:
The aircon cuts off at outside temperatures below 4or 5 degrees:rolleyes:,,id check earth points and alternator output ,because engines sometimes rev ..idle slightly higher when theres no alternator load on it ,and as wee all know low power causes all manner of faults when theres nout wrong ;)
Click to expand...
That's what the book states about the aircon, but once the engine has warmed up it seems to work at temperatures below 5C
 
Just when you thought it was safe to go back in the water, here I am again with my P37½ in need of help.

After all the brilliant input above, my dashboard has now returned to what passes for normal. Because I expected to have to wait a while for all the concealed irrigation behind the aforementioned dash to completely dry out, I waited before reporting back. and waited and waited and everything faded into the background dead files of my memory. At least until recently when the next problem(s) surfaced, which it inevitably did.

So, first things first, Thanks to all who got involved and my apologies for not saying so, sooner.

Where was I ? Oh yes, the next problem:

Members have helped me with solutions to every problem I have ever presented here. However I have not hitherto started off with the problem of how to explain the problem in the first place.

The car seems to have a throttle problem or possibly two separate problems.

The first is that when I start from cold, the engine idles evenly at 1500/2000 rpm, if you can call that idling. When I move off, the revs drop back slightly, but not enough to let the car just“creep”. Usually when the engine has warmed up, this problem seems to clear. I have no idea if it is in any way connected with the second problem or just a coincidence as the latter first appeared weeks later

The second problem is rather more of a trial and more difficult to explain. Intermittently, the car lurches as if trying to decide what gear it would like to use.. The rev counter bounces back and forth violently between 500 and 1800rpm.

Although it never quite cuts out completely, it sometimes feels as if it has fuel starvation, or a sticky carburettor problem that one remembers from long ago. I virtually lose control of the engine speed. If I lift off the hot tap the lurching stops but I am then doing about 5mph. Alternatively, pushing hard on the accelerator, and getting above about 2000/2500 rpm will clear it but I might well be moving faster than suits traffic conditions. Even then it does not clear instantly and I get a sudden increase in speed, such as I believe you can get with turbo lag and it is just a bit disconcerting. No doubt one of our wise members will ask if I have told my insurance people that I had bolted on a turbocharger !

The problem can occur without warning and in no obvious (to me) identifiable circumstances. It can happen whether the engine is stone cold or when it has nicely warmed up. It can happen at various speeds. It makes no difference whether I am using petrol or LPG, so this would seem to rule out contaminated petrol. I can drive for half a day, stop for a 5 minutes, re-start and the problem is back. Sometimes I can even go for days without it occurring at all. The biggest difficulty is that I can detect no pattern at all, although it sometimes occurs when going up hills and then I can sometimes counter it by dropping down a gear or two, although of course that is simply pushing the revs above my notional 2500rpm.

I hope that all this makes some sense but if someone asks fort clarification, I will certainly not be offended or surprised. I don’t even know if I have given too little info or too much.

So, does anybody recognize this scenario ? Have I even provided enough information ? Could it possibly be down to the gearbox electronics ? Could it be something inexpensive….please ?
 
Probably best to sort the idle speed first. Could be a variety of things, but check the usual suspects like:
  • IACV
  • Clean Throttle Body
  • Fix any air leaks (check inlet pipes, and LPG pipes between injectors & manifold.)
Might also be worth cleaning all the Engine ECU contacts, plus all the sensor & injector connectors.
 
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