Cold Starting Problem - Misfire, Hunting And Cutting Out

[will1991 11 1 Cars]

Hi all,

 

As you can see my post count is very low, but I've spent a HUGE amount of time trawling this site!

 

For reference, the car is a 100% standard '91 1.9 GTI with 56k on it.

 

I've got a starting problem - on start up from cold the car will misfire and if you don't catch the revs, will cut-out. Taking the car to 2.5-3k rpm will get rid of the misfire and then if you hold the revs at c.1500rpm for a few secs will then stick at about 1400rpm which then drops to about 1100 rpm before the SAD closes up. At this point the revs will hunt between maybe 500-1200rpm, often cutting out when coming to a hault in traffic.

 

Once the car has warmed up a bit, it'll run fine.

 

The car originally ran nicely without issue. It all went wrong following a service which saw all fluids replaced as well as fuel filter, oil filter, air filter, plugs, leads, dizzy cap and rotor arm with the throttle body, SAD, hoses, and AFM all cleaned out at the same time. Since then I've tried different leads, different cap, different SAD and new HT coil, none of which made any difference.

 

What did work was putting the old plugs back in, the car started well and without misfire about 3 times before reverting to being a pain - does this indicate something is wrecking the plugs? if so, what could it be?

 

Other things I know:

• There appear to be no air leaks - infact, before the car had starting problems it had a small leak at the sunroof T peice which was subsequently fixed.
  
• The vac advance appears to be working following the suck test
  
• the car cuts out as soon as the AFM is unplugged
  
• it cuts out when the CTS is unplugged
  
• I've tried adjusting the mixture screw to both extremes and everywhere in between with no success.
  

I know this is a problem that has come up before, but like I say I've been through the site over and over and feel like I'm running out of possible solutions - if anybody has any ideas or is based in Derby and has some knowledge or bits they's be willing to swap over to test my more suspect components I'd be really grateful.

 

I'm really annoyed at myself actually, its a fantastic, very clean car and my (well intentioned) service seems to have set it back some-what.

 

 

http://s234.photobuc...ot%20205%20GTI/

 

Thanks,

Will

[Richie-Van-GTi 71 2 Cars]

Its possibly an air leak based on the hunting, easily found with a can of carb cleaner squited around anywhere tht may leak whilst running, or its just poorly set up since cleaning, IE the balance between AFM, Dizzy and Idle screw. Haynes has a guide to initial set up to get it going.

[welshpug 1,657]

My 309 was pretty similar, I replaced the AFM with a re-manufactured one I had form my 205 (as I had converted to a non-afm setup)

 

worth checking the resistance across it as you move the flap, also check the CTS.

[will1991 11 1 Cars]

I also failed to mention that following the service I had the car set up on a rolling road hoping to have all the settings balanced out to get it running as it should. As part of this, the AFM was adjusted with the spring tention lessened slightly. Anyway, none of this appeared to have any affect on cold starting. I might have sent it back but I was then away for the following 5 weeks.

 

I'm hoping to get hold of an ohm meter to test some bits but as I said, they seemed to do their job prior to the service - perhaps I upset/broke something during removal.

Edited October 18, 2012 by will1991

[welshpug 1,657]

I'd definitely give it a check with the multimeter, there's an air temp sensor inside IIRC, and check the CTS.

 

all the figures and methods you need are in the Haynes Workshop manual

[will1991 11 1 Cars]

I'll have a go and report back, thanks.

 

Meanwhile, any other suggestions are much appreciated!

[PhilNW 44]

try the temp sensor that feeds the ecu

[UremaW 0]

I can't offer any advice as i'm experiencing exactly the same symptoms myself (so will be watching this thread with interest!), however just wanted to say that's a gorgeous car, Will. It looks brand new.

[Carbs4me 45]

You tried adjusting the cable? on the thottlebody its alittle thing on the far side of it to the left, try turning that so it pushes the thottle cable tight, and screw the mixture screw in, just keep playing with those until you get something your happy with, to me it sounds like the idle is dropping to quicking, and the ecu is trying to keep it running by bringing the revs up again. If it was an air leak, when you where driving you generally get burst's of power/flat spots if you put your foot down.

Edited October 22, 2012 by Carbs4me

[Kezzer30 40 1 Cars]

Mine does the exact same thing , only when its cold its not too bad when its been a mild night , ive had a chat with my mechanic friend he tells me could be condensation on the dizzy cap causing it to do so etc , hes going to sort it for me in a cuple of weeks before winter really sets in.

[will1991 11 1 Cars]

Right then, thanks for all the replies so far. I've been very busy at work recently so haven't been able to make much progress as yet.

 

Today I fitted a brand new CTS (by the time you've whipped the old one out and tested it etc I thought I may as well just pay the £10 and be done with it). Initial impressions are that it has made no improvement unfortunately.

 

I'm still wainting to borrow a multimeter to test the AFM, which is now looking pretty suspect. Can these be reconditioned?

 

I've sprayed carb cleaner over potential air leak areas but to be honest, once the car is warmed up and idling properly it doesn't really do much hunting. I suspect its more a case of what Carbs4me was saying re. the ecu trying to catch the revs when they drop too quickly - but why are they dropping too quickly? With regards to the cable, its at a point where you can JUST here it click before it hits the stop, which I thought was how it's meant to be set?

 

I've spent a long time playing with the mixture, dizzy and idle screw with no real success. I've looked for the section in my Haynes but haven't been able to spot it, if somebody could let me know the page number that would be ideal.

 

Thanks again for the help,

 

Will

[johnnyboy666 195 1 Cars]

cant help on page number, but there are two versions of the haynes, ones of them has more info than the other I think

[lagonda 42]

Second what Kezzer30 said. It sounds exactly like the trouble I had....condensation in the distributor cap. Easy enough to spot...as soon as the engine cuts out, take the cap off, & if you see condensation, that's your problem.

Had a lot of rain here recently & with the car parked over damp ground, have had it recur a couple of times.

If this is the answer, dry the cap thoroughly with tissue paper, refit and run the engine till it's thoroughly hot. Then take the cap off and leave it for a couple of hours....that will enable the distributor to thoroughly dry out. Should run fine then.

[will1991 11 1 Cars]

Evening,

 

Yesterday I managed to get hold of a multimeter and have now tested my AFM, as per the article on the main site, as well as an old 1.6 unit (not sure if this is/was working to be fair) to compare against.

 

My results showed the following (in ohms) when doing the flap test. I tested at each jagged notch on the wiper track too:

 

CLOSED - 190 (so too high)

Notch 1 - 580

Notch 2 - 660

Notch 3 - 700

Notch 4 - 720

Notch 5 - 750

Notch 6 - 760

Notch 7 - 795

Notch 8 - 800

Notch 9 - 805

Notch 10 - 680

FULLY OPEN - 700

 

The readings were a bit variable but would eventually settle(-ish) and the peak reading was somewhere between notches 8 and 9 at about 825.

 

The test on terminals 8/9 gave 291 - so OK

 

The test on terminals 8/5 gave 469 - a bit high.

 

 

So these results would suggest that my AFM isn't working as it should be, the figures are out and surely it shouldn't be peaking before the end?

 

The 1.6 unit I tried gave similar results but climbed more quickly and dropped much further at the end. The tracks on this looked pretty shoddy compared to mine so I suspect it's nack'd.

 

Would you agree the AFM isn't quite right? If anybody in the Derby area has a known working one they'd be willing to let me try I'd be eternally grateful!

 

 

I also tested the TPS which seems ok and I've also tried the set up as per Haynes to no avail. I'll be looking at whether the dizzy is damp and can be dried out in the next couple of days - maybe that'll sort the startup misfire.

 

Thanks for the help so far - the investigation continues...

 

Will

[Carbs4me 45]

The 1.6 AFM wont work correctly on the 1.9 engine.

 

If you have your AFM part number i may have one knocking about.

[Grim.Badger 15]

When you say you have adjusted the mixture, do you mean the screw on the AFM?

 

Also, as PhilNW asked, have you checked the ECU temp sensor, but also the connections to both the ECU temp sensor and the SAD?

[kilauea 7]

Just got my 205 running again after a yearish off the road. Very similar issues and as per Kezzer and lagonda - it was damp in the dizzy and round the plugs.

Squirt of wd40 later and fired first time and it's back to it's usual zero hunting tickover at 1100rpm.

[will1991 11 1 Cars]

Sorry I've been so inactive, been really busy recently.

 

In terms of mixture, yes I've only adjusted the AFM screw, so idle mixture only.

 

Is the ECU temp sensor different to the coolant temp sensor? I've replaced the CTS, but haven't checked the connections, am I looking for a certain voltage from those?

 

In terms of misfire, I've had the dizzy cap off once the car had warmed up and let it dry (assuming there was actually some moisture - didn't appear to be any in the cap) but that has made no difference. I also had the car in France for 3 weeks of this year with no rain and it still missed.

[Grim.Badger 15]

You shouldn't really need to play with the AFM mixture screw, and I'd try to avoid it unless you're 100% sure everything else is working - I don't remember why, but I think its because its awkward to get right iirc

 

The ECU temp sensor has a blue double "junior timer" connection and should be around the SAD or the coolant temp sensor and switch somewhere (Peugeot used at least 3 different positions for it). The wiring could well be brittle and corroded inside causing a bad connection and wrong signals even if the sensor is new.

[pug_ham 244 3 Cars]

try the temp sensor that feeds the ecu

 

Also, as PhilNW asked, have you checked the ECU temp sensor, but also the connections to both the ECU temp sensor and the SAD?

 

AKA the CTS (coolant temp sender) as suggested by Mei earlier;

also check the CTS.

Since you have a H reg phase 2 there are two places you will find this fitted, either in the coolant temp sender housing bolted to the bottom of the thermostat housing underneath the distributor or at the back of the thermostat housing under the two senders for the dash.

 

I suspect it'll be the later of the two, as shown in the middle of the three pictured below;

 

 

But, if you have changed it as stated above you'll already know this.

 

Have you checked the internal cleanliness of the throttle body & for any disturbed split pipes that might have been disturbed during either the service or rolling road?

 

Where did you take the car for this rolling road & was this problem apparent immediately afterwards when you next started the car from cold?

 

g

[Richard309Sri XU5JA 205GTi 8]

Hi was there ever a solution found? I have the same problem. I am not sure if this thread is now archived? 

If anyone can continue the discussion I need some help trying to sort out the same problem,

I have the 1.6 gti xu5ja engine in a 309 but it is exactly the same as the 205 1.6 l le2 jetronic system 

[309SRiguy 15]

Hi Richard,

What are your particular problems? The misfire, the surge in revs, the sudden shut-off of revs, cold starting, or all of them?  

Have you followed the set-up in 309 manual (Coomber)?

With my 309SRi I have finally reached a stage where it is driveable in traffic without too much frantic footwork being needed to keep it running. It still stalls often for the operator at the testing station though.

 

List a few of your symptoms with a bit of detail and I'll see if I can help.

 

[Richard309Sri XU5JA 205GTi 8]

Hi Bryan,

 

Thanks so much for your reply. 

 

I actually finally got my engine to idle and rev. ok :)))))) ,

 

although I must confess I think the timing is not right. I need to dynamic strobe. light set up. I got an ok one from Amazon and will do this week. The only other thing is the radiator fan has not cut in and out. so I need to check that as to use it on the road would obviously be a risk without the rad. and the fan to be proved working.

 

Can I send you a video of it running so you can see what you think about the timing? 

 

There is good spark on all plugs though I have checked them individually.

 

Some of the things above in this thread were right,some not relevant to me anyway and some very important things I did are not listed above. 

 

I haven't seen the 309 manual(coomber). I'll look for that now. I have the haynes if that is similar, and also I have got the RTA from France and a french book about restoring the 205 GTi "Restaurez ...votre ....205GTi" . As our engines are the same this book was really good;actually of course a lot of the 205 car is the same as the 309.

Easy to learn a bit of French as the pictures are great. 

 

Ah right - it is interesting to know you still have some stalls; so I won't worry too much if that happens to mine 

anymore. It did stall yesterday actually.It does that when you accelerate then it like the inertia of the engine slowing down kills it. There is a fine line between idle and stall I guess;chasing the holy grail, that magic number of 14.7 fuel air ratio programmed into the ECU;I am not sure what my emissions are like currently.

 

You must have the LE2 jetronic system(?) In my opinion it is good for it's time I guess it has fallen behind a bit now as there is no lambda sensor. I am planning to try and get mine MOT'd in the UK. I hope it will pass the emissions test. The last time I passed the MOT was 2014. I changed the engine because there was a small crack in the block and it was leaking. I have a bit more work to do on the brakes but then it is all little bits and pieces like the rear wipers, washers seal belt stuff like that. I have done loads more than I thought I could. I only have a small garage on a semi detached house and a drive.Im not a full time mechanic but managed to rebuild an 205 gti 1.6 engine, new piston rings, new jacket seals new head gasket. New Sachs Clutch. Hope it will pass the MOT I want and need to get it on the road to test it further and enjoy the hard work. 

 

Anyway yeah I can send you a video I think to see what you think of the idle I have now? 

 

Thanks for the message again great to hear from you especially as you have the same model