Mk3 GTI Loosing revs!

[Pernicitus]

Hi all,

I have a problem with my R reg GTI. I have looked through alot of the other posts and I don't think it has been covered so far (opps if it has)

Anyway, before any of this started, I could take the engine right up to just above 6000 RPM, then just as it would red line it would loose power. Fair enough, its been limited I thought, saves me blowing the engine!

The GTI needed a clutch change, so I dropped it into a local garrage to get that done, when I got the car back, the clutch was excellent etc, Cool.

Next day as I was driving it, I excellerated and at 5000 revs the engine started to splutter!!! When I change up gears, no probs untill I hit 5000 revs again and the same prob????

The car starts to jerk violently as soon as 5000 is reached. Its as if the engine is being starved of air or fuel or sth!

I cant see what the connection (if any) is with a clutch change, but it happened just after it.

Any Ideas?
Any helps appreciated.

Cheers Pernic

[Pernicitus]

OK so I got my hands on a laptop from a friend of mine, with Vag-com software installed. I checked the car out with it and it came up with a few errors!
3 Faults Found:
00525 - Oxygen Sensor (G39)
03-10 - No Signal - Intermittent
00537 - Lambda (Oxygen Sensor) Regulation
19-00 - Lower Limit
00525 - Oxygen Sensor (G39)
03-10 - No Signal - Intermittent

When I clear these faults and go for a drive, the car is back to normal. The revs go right up to 6000+ again. If I turn off the engine and restart the engine again, the problems reaccur!

Has anyone ever come accross these types of errors before? Or even know what "Lambda regulation" is?

Are these sensors hard to replace?

The final reading I did yesterday came out like this:
Saturday, 25 August 2007, 09:50:52
VAG-COM Version: Release 409.1-S

Control Module Part Number: 037 906 ----
Component and/or Version: SIMOS 4S 2104
Software Coding: 00000
Work Shop Code: WSC -----
6 Faults Found:
00625 - Vehicle Speed Signal
16-00 - Signal Outside Specifications
00537 - Lambda (Oxygen Sensor) Regulation
19-00 - Lower Limit
00525 - Oxygen Sensor (G39)
27-10 - Implausible Signal - Intermittent
00525 - Oxygen Sensor (G39)
03-10 - No Signal - Intermittent
00515 - Camshaft Position (Hall) Sensor (G40)
16-00 - Signal Outside Specifications
00525 - Oxygen Sensor (G39)
03-00 - No Signal

Oh God! Help :confused:

[Col]

Try swapping the fuel injection system relay, the grey one.

They are cause all manner of problems and as you are getting so many faults I'd think it'd be my Nr.1 suspect.

About £20 from VW bless em.

[Pernicitus]

Cheers Col for the reply,

The fuel relay, Hmmm I will have to have a look in the morning for that and order one from local VW Garage, could it really be causing all those problems tho.

I suppose it might be the case when I think about it alright, When I clear the faults with the laptop and rescan the engine, it comes up clean, its only after a short drive or so that the apperent faults reappear!

Hmmmm sounds promising!

I'll try that out and keep you posted,
Thanks again!
Pernic

[Huweth]

Could it also be that the mechanic who changed the clutch has not connected the sensors up properly if he needed to unplug them?

[Bostrom998]

Hi, I have had this problem before on a 1999 golf 1.8.

If I remember correctly the mechanic had forgoten to connect a very important earth strap onto the gearbox after fitting a new clutch.

The earth strap normaly runs down from the battery area & should be connected to the gearbox case.
(With this lead left disconnected it may cause damage to other sensors as they will be used as substitute earthing pionts- thats why you get so many nutty trouble codes.)

Best of luck & let us know what you find.:beerchug:

[Pernicitus]

Long day at work today, didn't get a chance to do much about the relay, I did have a look at the relay/fuse pannel, I have several grey relays in there. There are two dark grey ones and one light grey one in the bottom right of the pannel. Is the fuel injection system relay, this one?

Earth strap? Hmmm very interesting! I will defo have a look at that tommorow, just have tofind the time somehow!

Thanks guys for the info, I will have a look at those tommorow,
Oh BigCol, Do you know which one that relay is?

Cheers again

[Pernicitus]

Got the new relay yesterday, it was the light grey one in the bottom right of the box, no 167 on the outside and 191906383c written on the side. There was no fuel injector relay, but this one is labled as fuel pump relay.

So I swapped it out and cleared the faults and went off for a drive, same problem occured grrrr, I checked the faults with the laptop and they were all back also!

Then I checked the earth lead, It is connected to the gearbox alright, I wonder if it should be removed and the edges of it sanded for better contact? What do ye think?

I will have to take another look at the relay box to see if there is another relay I could have missed?

Any other ideas?

[mo_schino24]

i ahve the exact problem, im gonna change the 02 sensors on tuesday, got them ordered. ive already changed the distributer cap, rotor arm, spark plugs and leads, fuel filter, oil changed, if the 02 sensors dont seem to work, then id be heading for the coil pack and change the ground wire cos it looks bad to me, the one conected to the coil pack.. ok bye now.. on the mission to find that problem!!

[Pernicitus]

Interesting! You are having similar probs to me. Id be very interested to hear what happens after sensors are swapped.

Drop us a line when you get the car back.

Cheers

[Crasher]

You problem is linked to the distributor hall sender fault code. If the position of the distributor is incorrect, the ECU is not able to initiate sequential fuel injection and subsequently will rev limit the engine to around 5000 rpm. Using VAG-COM and with the engine idling, you need to put the ECU into measuring blocks 08, sub group 007 and look at the figure in display group 1 which should be between 57 and 60 or 1 and the figure in display group 2 which should be between 5 and 8. Rotate the distributor slowly as required to get the figures reading within the specifications.

[Pernicitus]

Using VAG-COM and with the engine idling, you need to put the ECU into measuring blocks 08, sub group 007 and look at the figure in display group 1 which should be between 57 and 60 or 1 and the figure in display group 2 which should be between 5 and 8. Rotate the distributor slowly as required to get the figures reading within the specifications.

Enclosed I have logs from the car,
The Group 1 is 61 which is a little over and group 2 is 61 which is miles over! How do I get these down?

the second pic shows the O2 sensor which is out of bounds at 1.56

Any help Crasher?

1062

1063

[mobitune]

Sorry to hijack, just a quick query... crasher - where did you get that jpg from? Is there a file with all the codes in it? Just interested to know if i could get my hands on it.

Pete

[Crasher]

Pernicitus, start the engine and bring up that screen again, slacken off the distributor 13-mm clamp bolt and rotate it as you would for setting the timing on an older Golf (rotating the distributor has no affect on the timing of an AGG engine, in fact the engine will run with the hall sender unplugged). Slowly rotate the dizzy one way and if the readings get worse, go the other way but a tiny movement will make a big difference and the screen will take a moment to alter for each change of dizzy position so make a move and wait. The lambda error may go away when the car is running correctly.

That data is a printout from ELSA cropped and altered to fit the page. PM me your email address if you want a full list of AGG engine codes.

[Pernicitus]

Nice one Crasher!

Not knowing much about engines, I proceeded with caution. I setup laptop and started engine. I was about to loosen the clamp bolt and I noticed there was a three pronged connector sticking out of the distributor assembly with nothing connected to it ( probably hall sender unplugged). A quick scan around the area showed a connector which had broken off and was conviently placed out of view around the back of the distributor unit!

The connector when fitted, juts out a little over the gearbox. That F%ck$£g mechanic that I left it into must have broke it off and then placed it out of view around the other side of the distributor!

I taped it back into place and the revs+sound of the engine changed slightly. I checked the laptop and sure enough the first group read 58 and the second group reads 5!

I cleared the faults and took the car out for a spin. I checked for faults again after I got back and got these results :
3 Faults Found:
00525 - Oxygen Sensor (G39)
03-10 - No Signal - Intermittent
00537 - Lambda (Oxygen Sensor) Regulation
19-00 - Lower Limit
00513 - Engine Speed Sensor (G28)
16-10 - Signal Outside Specifications - Intermittent

I suppose this might mean that the oxygen sensor needs changing after all.
Maybe the lambda regulation and the oxygen sensor faulst are linked?

What do ya think? Oh anybody know if getting the O2 sensor changed is a big/costly job?

Thanks again Crasher, you saved me alot of time and money!
Cheers bud!
1065

[mo_schino24]

i could recommend you a mobile mechanic if u live in London, i got mine changed for £20 but had to buy the 02 sensor for £99 from dealer, mine when taken off, was filled with oil and carbon so it was worth changing even tho the problem exist, however seem to have some improvement, but my next move is to wait for my catalyst to be changed which is under warranty. must be clogged that's what.

[Pernicitus]

i could recommend you a mobile mechanic if u live in London, i got mine changed for £20 but had to buy the 02 sensor for £99 from dealer, mine when taken off, was filled with oil and carbon so it was worth changing even tho the problem exist, however seem to have some improvement, but my next move is to wait for my catalyst to be changed which is under warranty. must be clogged that's what.

Cheers for the shout back Mo! So has the reving problem been fixed yet or is is still there? You said that there was some improvment but what exactly?

Oh I'm nowhere near London at the mo but thanks any way :beerchug:

[Crasher]

The lambda sensor may come back to life when the car has been run for a while but the engine speed sensor is obviously playing up and this is common. If you replace these two sensors, I would recommend you used genuine VW parts (the speed sensor is very expensive from VW and aftermarket ones are temptingly cheap but fail quickly) or a Bosch lambda sensor and a VDO speed sensor. Check the lambda sensor plug on the right hand rear engine mount bracket is plugged in and the wiring isn’t damaged