Regarding my cold start issue... don't want to say too much in case I jinx it, but I think I might just have cracked it! Will report back after further testing but it involved the fuel pressure gauge, replacing the WUR and performing my own DIY version of the Stealth WUR mod using some assistance from Mr Black & Decker powerdrill and a 4mm allen key Fingers crossed!
Yep - it's looking good. Last night with the replacement WUR fitted the cold control pressure steadily rose from 1 bar (14.5psi) up to 3.1 bar (45psi) when warm, that took around 3 mins. The car seems to start fine from cold and run much smoother now. Just because I could I decided to take the WUR off again and drill the back like Steath do, then I adjusted it to give 3.3 bar (48psi) at hot idle. Tried it again today from cold and the control pressure rises from 1 bar to 3.3 bar now over about 3 mins - smooth idle too! Not counting my chickens or anything but I think I may have sorted a problem that's been plauging me for 6 months or more! Will report back after more testing but thanks to everyone that helped out, particularly 150pdgti, Golden, GTI, Pigbladder and Iguana for the WUR! Edited by: Stu
okay..ive done some more work to it ive drifted the spigot to ajust the cold pressure to around 20psi, which i figured is about right for today now...while warming up it "hunts" i think thats the term...the revs sound like broom broom but when its warmed a little, say 30 odd psi it settles to an even idle one more question...the main control pressure, what effect does having it towards either end of the accepted range have to the running /drivability?
dunno if anyone is still following this [:^(] anyway just been for a test drive and its the same..jerky/kangeroo when moving away from a cold start thing is ive ajusted the shimms in the metering head and hot/cold wur pressure and NONE of these changes made a slight differance to my problem( it does seem a bit faster though ) so im thinking its sod all to do with the inj system anyone got any ideas..something thats there in first few moments of running thats not when warm? i just cant keep spending on it
PB - I'm still following it, don't worry! I will have a think and post up an ideas I have when I have them! At the moment I'm thinking a blockage in a fuel line, faulty pump or accumulator or similar but it's probably not of those things! How about a vacuum leak somewhere that only occurs with a cold engine and heat expansion closes it off as the car warms up? It's a thought!
yeah ive tried another wur..drives just the same a vac leak does sound possible, ive changed all the flexi vac hoses and checked the rubber pipes stu..if possible some time could you hook up the gauges and report back with a mfa outside temp and the readings every 15 secs, then i can do the same when its a similar outside temp oh one more thing...the car has always revved to 2k on cold start, which im told should be nearer 1500..does this sound related to anything Edited by: pigbladder
i dont know why but since i swapped my isv for another one(yesterday) the car not only idle's alot better when cold but it seems to run alot smoother too? its weired!
yeah it kinda makes me wonder if the isv cant open quite enough when the engine needs it most trouble is its a mugs replacing parts that way..and 2nd hand are often dud anyway Edited by: pigbladder
today i disconected the red/blk wire at the coil and test drove it i managed to idle down my road with no jerkyness at all with no throttle so that makes me think duff isv or controller( i have already swaped em both) any ideas how i can tell which one is dud? i spose this eleminates the inj pressures although i wont speak too soon
Try disconnecting the cold start valve altogether and starting the car from cold. I had the same symptoms and Stealth had the same success as they had with yours.
