Hi all. I hope someone out there can help me. i have a 505 GTi 1990 wagon. she was running perfectly. a few months ago, i decided to try to fix the dash panel under the drivers side, which was hanging a bit low, making it really difficult to access the bonnet release. zip tied a few things up to solid bars, carefully avoiding any wiring. (double checking this, all seems fine) drove her a short distance - all ok. the next day, started beautifully as ever, but wont rev past about 1750, missing, backfiring and almost cutting out. thus started the checking and replacing! replaced plugs, no change, checked them and all fine. tested HT leads, fine. pulled dizzy cap off, seemed fine, no cracks. fuel is fine. checked for air leaks, none. seems we have tried everything and nothing is making a difference. i think a few other things were checked, but i cant remember now! one website suggests it is often the last thing you did before having problems, ie under the dash. is there anything under there that could be causing this problem? thanks in advance if you can help. Michele.
505 GTi wagon wont run past idle
- Thread starter Michele
- Start date
Welcome to the club! My DS21 has a similar problem. Mine won't go past a bit over 2,000rpm. This happened after I replaced the capacitor with a new one after which I could not even get it to start. It did eventually run for a few kms then power dropped off drastically on the way home. I hope someone can point you to a fix of your problem.
Don
Don
From the symptoms, it sounds like you are not getting enough spark, either from the coil shorting out internally, or the pickup coil inside the distributor shorting internally.
However if you are adamant that it had something to do with the dash work, I have covered both possibilities in a post on a different thread :
https://www.aussiefrogs.com/forum/p...lp-needed-1988-peugeot-505-gti-mystery-2.html
Inside the tachymetric relay looks something like this :
Here is a little blurb on tachymetric relays which may or may not be relevant : http://www.505turbo.com/forum/index.php?/topic/3466-505-tachymetric-relay-replacements/
However if you are adamant that it had something to do with the dash work, I have covered both possibilities in a post on a different thread :
https://www.aussiefrogs.com/forum/p...lp-needed-1988-peugeot-505-gti-mystery-2.html
Inside the tachymetric relay looks something like this :
Here is a little blurb on tachymetric relays which may or may not be relevant : http://www.505turbo.com/forum/index.php?/topic/3466-505-tachymetric-relay-replacements/
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Agree the tachymetric relays are notorious for failing however my understanding of how they work is that they cut power to the fuel pump (as a safety measure) so would have thought the car wouldn’t go at all if it’s failed - worth trying another if possible to eliminate this as the cause.
Also check the fuel pressure regulator (little metal canister on top of fuel rail towards the front). Mine stopped dead in its tracks when this failed though I imagine different failure mode could cause other symptoms such as you’ve got. Mine failed a few weeks after I’d discovered the rubber pipe from inlet m/f to canister had utterly perished, replacing this solved a non-starting issue, ran brilliantly for a few weeks until regulator failed - long story
Cheers
Baldrick
Sent from my iPhone using Tapatalk
Also check the fuel pressure regulator (little metal canister on top of fuel rail towards the front). Mine stopped dead in its tracks when this failed though I imagine different failure mode could cause other symptoms such as you’ve got. Mine failed a few weeks after I’d discovered the rubber pipe from inlet m/f to canister had utterly perished, replacing this solved a non-starting issue, ran brilliantly for a few weeks until regulator failed - long story
Cheers
Baldrick
Sent from my iPhone using Tapatalk
hi again and thanks again for suggestions. i am not adamant...about anything! we are at a loss now. i pulled the tachy relay off today and checked it with a magnifying glass for cracks, cant see any plus all the transistors and other bits are firm when i tried to move them (gently) with tweezers. will check the fuel pressure regulator, thanks so much for your help.
My 504 began playing up, idle would die down, occasional cutting out altogether. Almost ready to blame failure of the Simon BBC electronic ignition kit installed about 3 years ago. Some indication of problem was the rev. counter needle would fall back to zero.
Have disconnected rev counter wire at coil, no further problems so far ?
Have disconnected rev counter wire at coil, no further problems so far ?
^ Good suggestion, and easy to try.
OK OK OK....let's get back to basics.....we need to separate the problem into two : is the problem with fuel, or spark ?
Pour some petrol down into the air intake and see if it still backfires ?
It SOUNDS like a spark problem, but what is the reality ?
OK OK OK....let's get back to basics.....we need to separate the problem into two : is the problem with fuel, or spark ?
Pour some petrol down into the air intake and see if it still backfires ?
It SOUNDS like a spark problem, but what is the reality ?
Good suggestion, the cat. How would you check? Unhook the exhaust and give it a run?
Does it run an o2 sensor??
If so grab an old sensor, drill it out and replace the working sensor. Before the exhaust gets hot shove a low pressure gauge into the drilled out hole and rev the engine.
On my old cat-less Fuego doing this gave a result of next to no pressure, so I don't know what type of pressure you'd expect from an exhaust with a healthy cat, but I'd guess it to be on the low side.. a few psi at most.
You'd probably also get hints by doing an inlet manifold pressure (vacuum) test.
More on that here....
https://www.motor.com/magazine-summary/mastering-the-basics-reading-a-vacuum-gauge/
Jo
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There will be a limited volume coming out the end of the exhaust pipe !!
Is the carbon brush in the centre of the dizzy cap free to slide in and out or warn out?
Well, yeah, but assuming you don't have a baseline with a healthy cat, that's not going to be clear.
Michele,
found there's a previous post for 505 with almost same symptoms
http://www.aussiefrogs.com/forum/pe...fectly-but-runs-very-roughly-higher-revs.html
bit inconclusive but there may be some more pointers there
Regards,
Rob
found there's a previous post for 505 with almost same symptoms
http://www.aussiefrogs.com/forum/pe...fectly-but-runs-very-roughly-higher-revs.html
bit inconclusive but there may be some more pointers there
Regards,
Rob
we were getting her ready to take to the local mechanic/auto electrician yesterday, when my partner tried taking the HT leads off one at a time. turns out 2 cylinders arent working! both have spark in plug and lead. He then remembered a time years ago when a friend's VW suddenly stopped while driving. turned out it was trying to fire on the exhaust stroke on 2 cylinders. we will check the dizzy again on the weekend. thanks for all your help. M.
Am I right in thinking that the injectors are electrically paired? This happened to one of my Gtis some years ago but I cant remember the exact details or the solution.
Could be paired spark plugs, rather than injectors?
Could be paired spark plugs, rather than injectors?
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FURTHER TO MY PREV POST.
Problem still exists, now located, this time for sure, Radio suppressor on the coil, removed, all's well. Next move throwing suppressor into the sea!
No difference to radio reception, why do we need them?
Problem still exists, now located, this time for sure, Radio suppressor on the coil, removed, all's well. Next move throwing suppressor into the sea!
No difference to radio reception, why do we need them?
Try AM for reception. FM will be too high to pick up spark noise.
So, as far as I can make it, the OP has found the problem? If HT leads work okay and engine works on two cylinders, the HT leads may be misplaced (wrong plug). Swap the two around and see what happens.
So, as far as I can make it, the OP has found the problem? If HT leads work okay and engine works on two cylinders, the HT leads may be misplaced (wrong plug). Swap the two around and see what happens.
hello again all. sorry, i am not ignoring you! partner had a planned hand operation last week, so i have been nursing and driving.
suspecting that we had been trying to run it on the exhaust stroke, ie crank position 360 out, we took the dizzy cap off to ensure the rotor arm was lined up with the notch in the dizzy housing when #1 was just before TDC and cranked by hand another 360. this time, removing every HT lead in turn resulted in it stumbling as it should, not just 2 cylinders.
Peter, re electrically paired - dont know, will check this, thanks!
HT leads are correct (triple checked!), but an early post suggesting we had only 'an idle amount of fuel' led us to check the throttle position switch. seems dead at anything but idle. will replace that and report back! thanks again everyone.
suspecting that we had been trying to run it on the exhaust stroke, ie crank position 360 out, we took the dizzy cap off to ensure the rotor arm was lined up with the notch in the dizzy housing when #1 was just before TDC and cranked by hand another 360. this time, removing every HT lead in turn resulted in it stumbling as it should, not just 2 cylinders.
Peter, re electrically paired - dont know, will check this, thanks!
HT leads are correct (triple checked!), but an early post suggesting we had only 'an idle amount of fuel' led us to check the throttle position switch. seems dead at anything but idle. will replace that and report back! thanks again everyone.