Ians3422
23-01-2008, 09:25 AM
Car is a '91 GTi 8V with 166k on the clock. I was given the car last year after it suffered a battery earth fault which sent the ECU faulty & flooded the whole engine with petrol. I got her up & running last year (with help from Crasher on the old VW forum - cheers mate!) and she's perfectly drivable but ive still got a couple of problems to iron out:
1) ECU - the original ecu number ended '022 DB' but at the time I could only get an '022 N'. It ran fine but I was told the '022 DB' ECU would run smoother as it's a later version. I managed to source one and swapped em over & she ran better, but had a problem that when coming off the throttle the revs would quite often stick at about 1600rpm; you had to 'blip' the throttle in neutral to bring the revs down to idle. Thought it was a mechanical problem (sticking throttle cable) but it was'nt, so the 'DB' ECU was discarded & replaced with the 'N' unit - until last week when I got hold of another 'DB' unit.
Fitted it at the weekend and it's doing exactly the same as the other DB ECU!!!!!! Can anyone help with a possible cause??? Does the Digifant management have a diagnostics port as my brother has a fault code reader he uses for his mk3 8V Gti?
2) If the engine is driven for a while (10 miles or so until properly warmed up) then stopped for a few minutes (to get petrol), when restarted it revs at about 1800-2000rpm and wont drop to idle for quite a few seconds, anyone seen this before? This happened with N type ECU - havent tried it with the new DB ECU yet.
3) Am gonna change the timing belt soon & set the timing, does anyone know how to test the Knock sensor? Is there anything else I should check & how? Haynes manual says the timing should be set at 2000-2500rpm, when the dizzy should be turned until the pointer on the flywheel/ bellhousing lines up. I was gonna set the timing at 2250rpm, is this right? Haynes also says to check the Hall sender & blue temp sender, although I changed the temp sender last year & am assuming car wouldnt run with a faulty Hall sender?
4) Gearbox - ive seen a low mileage gearbox for sale from an older EV engined Jetronic GTi 8V - it looks like an 020 type, will it fit my PB engined car and will the ratios be the same?
Any advice from your previous experiences greatly welcome!
1) ECU - the original ecu number ended '022 DB' but at the time I could only get an '022 N'. It ran fine but I was told the '022 DB' ECU would run smoother as it's a later version. I managed to source one and swapped em over & she ran better, but had a problem that when coming off the throttle the revs would quite often stick at about 1600rpm; you had to 'blip' the throttle in neutral to bring the revs down to idle. Thought it was a mechanical problem (sticking throttle cable) but it was'nt, so the 'DB' ECU was discarded & replaced with the 'N' unit - until last week when I got hold of another 'DB' unit.
Fitted it at the weekend and it's doing exactly the same as the other DB ECU!!!!!! Can anyone help with a possible cause??? Does the Digifant management have a diagnostics port as my brother has a fault code reader he uses for his mk3 8V Gti?
2) If the engine is driven for a while (10 miles or so until properly warmed up) then stopped for a few minutes (to get petrol), when restarted it revs at about 1800-2000rpm and wont drop to idle for quite a few seconds, anyone seen this before? This happened with N type ECU - havent tried it with the new DB ECU yet.
3) Am gonna change the timing belt soon & set the timing, does anyone know how to test the Knock sensor? Is there anything else I should check & how? Haynes manual says the timing should be set at 2000-2500rpm, when the dizzy should be turned until the pointer on the flywheel/ bellhousing lines up. I was gonna set the timing at 2250rpm, is this right? Haynes also says to check the Hall sender & blue temp sender, although I changed the temp sender last year & am assuming car wouldnt run with a faulty Hall sender?
4) Gearbox - ive seen a low mileage gearbox for sale from an older EV engined Jetronic GTi 8V - it looks like an 020 type, will it fit my PB engined car and will the ratios be the same?
Any advice from your previous experiences greatly welcome!