Beaker™

But you 'may' be lucky and find that your battery just needs replacing. It has been known that a weak battery can throw up codes.

Done some digging for you..... 17841-Secondary air pump relay J299 open circuit Tied in with A/C I believe too, if the C isn't running it, or for that matter the secondry pump heres your problem 17840-secondary air control valve N112 P1432 N249 Bypass done incorrectly? Split hose? 17526-02 heater circuit (bank 1-sns 2) open circuit (P1118) Possibly tied in with the secondary air pump problems, check to see is he has the pump or not. Bank 1 sensor 2 resistance too high (P1114) Crank position sensor or knock sensor may be on its way out, or not connected. Can-bws power trainmissin message ABS ECU (P1649) ABS been plumbed in or not? Or possibly using the Rado ABS pump and not a newer one which links to the 20VT? Or the ABS ECU is faulty, clear to see if it comes back or write out. 17978-engine ECU blocked P1570 error intermitant Again, clear and see if it comes back. May have something to do with the engine swap and the engine tried to be fired without the transponder ring, clocks, ecu and keys all matching. Failing that a faulty connection to the transponder ring can cause this. 17705-turbo/throttle valveconnection pressure loss (P1297) Again check the hoses around the N249 area, replace all for silicone. Or it again could be due to the progress throughout the conversion... been fired without all complete parts. Clear see if it returns. 16684-misfire recognised P0300 Spark plugs or coil pack, give it some new plugs anyway! 16685-cylinder 1 misfire detected P0301 If still returns once given new plugs, coil pack is also needed. 16486 mass air flow sensor 670 signal too low P0102 Dead MAF.

Well i'm not overly clued up on codes but...... i'd say change coilpack on cylinder #1 or at least swap them around abit and see if the code follow the coilpack. Also get your MAF changed. IIRC its £70 + your old one at the dealers. Then re scan for codes. Either that or post the codes on a mk4 Golf forum maybe?

If your definatly getting a misfire fault code then at least one coilpack will definatly need replacing.

That method will only reveal a totally knackerd coil TBH. The 1st signs of a coilpack going are misfires under load. Which will not affect idle.

Cheers mate :)

Good luck :)

No probs, worth check codes again though one more time as it may be the lambda probe after all.

That sounds promising, usually coilpacks will throw up some kind of 'misfire under load cylinder #' etc when they are starting to fail. Simple fix if it is that :) If you check the part number of the coilpacks (pull off the plug at the top, its under that) you may find you have early revisions, ie the part number ends in the letter H, or I etc. The later revisions, ie higher letter are alot more reliable and last alot longer. IIRC the latest revision is 'L' for the 'AYP' engine code, not sure on 'AUG's TBH. But worth noting that if they are all the same revision on your car then they may all fail one after the other :( I've had all four of the early types go in as many weeks before now. Since fitting the 'L's i've had no problem (8 months ago now)

Well it almost certainly sounds like a coil pack. Find out what codes were thrown up and stick em up here when you can :)

Sounds good, thanks for that. Being a NA engine it should also hold that curve longer than the Ibiza's though surely, our 1.8T's curves do drop soon after peaking. Cheers for that guys. :)

Well as its not mapped it can't be a mapping issue. If you know of anyway you could borrow coiplacks and MAF that would save spending out. Another possibility is the N75 valve, that could cause a random boosting issue. You have a boost gauge?

Hmm, my 20vt would hesitate and hold back soon after i got it. Would be very random as to when/where in the revs it would do it. Couldnt figure out for the life of me what it was, no fault codes. But somwhere in between changing the MAF, the remap and all four coilpacks the problem was solved. Yours remapped at all?

No not remapped as yet, 210/220 was about what we'd guessed. And that asuming of course then engines been looked after. What sort of torque figure should it be seeing? Also, can anyone recomend a good remap?

If thats the case the MAF should be fine. If the MAF is faulty then the car should run better with it unplugged. As for coilpacks, no real way of telling until they get so bad the car splutters and struggles to idle. In which case you unplug each one, one at a time and start the engine. When the faulty pack is removed there will be no change to the lumpy idle but if a good one is unplugged then the car will die (as only running on 2 cylinders). But until they get to that stage i dont think there is a way to tell. Know anyone who could lend you a lambda probe to try? What are the actual codes that are being thrown up?