loks Posted June 4, 2004 Share Posted June 4, 2004 I recently had the CW downpipes fitted to my TT (along with a plug change) and ever since I have had a misfire problem when I get to 1 bar pressure. Anyone else have this problem before? Below the 1bar the engine runs perfectly with the very very occassional 'lump' misfire when idling. My local tuner reckons that it is a air/fuel problem due to the cats being removed and I need to fit a bigger fuel pump (std at the moment) to cope. Does this sound logical? For your information I have carried out the following checks: 1. Changed and checked plugs. 2. Changed shagged connector housings (above coil packs) with new ones. 3. Made a fruitless search for a leaking boost hose. 4. Fitted TRL VFCC. 5. Checked the ! triangle does not light up during problem misfire. On maybe the same issue (?) I saw something interesting ("yawn") the other day. I was under the bonnet on the leaking boost hose trail and noticed the when the revs were increased the upper boost pipe from the intercooler into the fuel housing body was swelling up quite a bit. Is this normal and are the supplied intercooler Blitz pipes prone to high boost problems? What make would you recommend to replace these if necessary? Any advise would be hugely appreciated. Quote Link to comment Share on other sites More sharing options...
Alex Posted June 4, 2004 Share Posted June 4, 2004 Which plugs did you fit? If they were NGK's what gap did you set them to? Quote Link to comment Share on other sites More sharing options...
loks Posted June 4, 2004 Author Share Posted June 4, 2004 Denso IK22's Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted June 4, 2004 Share Posted June 4, 2004 "Changed connector packs" Que? Did you just chnge the connector plugs for the coil packs, or the whole complete loom, with connectors? The coils are polarity concious, if the little female connectors are put in their plastic shrouds the wrong way round then you get odd misfires and a lumpy idle. I had this last year, someone had broken some plastic connectors, and got new plastic bits from another loom, but pushed the connectors themselves in the opposed way around. Took AGES to find as they didn't tell me they had been working in that area... Costly ommission Sounds electrical to me. Quote Link to comment Share on other sites More sharing options...
loks Posted June 4, 2004 Author Share Posted June 4, 2004 Chris, Just changed the female connectors and not the whole loom. Have checked the workmanship and connection direction and they both seem ok. But I'm still with you and feel that the problem is electrical and not fuel related. Where to go now? Don't tell me to put it on a ship and you'll take a look at it and I've already told you that I have been working in that area Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted June 5, 2004 Share Posted June 5, 2004 If the connector spade terminals have been out of the plastic parts of the connectors suspect that the spades have gone back in the wrong way around on one or more plugs. I have 3 MKIV's here, I can look on Monday to tell you which wire goes to which coil terminal on cars that haven't been fiddled with. Quote Link to comment Share on other sites More sharing options...
loks Posted June 6, 2004 Author Share Posted June 6, 2004 Cheers Chris, appreciate it I hope to get me box brownie out later today and get some photos up on here. Quote Link to comment Share on other sites More sharing options...
loks Posted June 12, 2004 Author Share Posted June 12, 2004 Chris, You will be glad to know that it was an electrical problem. Some new HKS S45i's replacing the new Denso IK20's (garage told me they had fitted IK22's!) No misfire. Quote Link to comment Share on other sites More sharing options...
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