miko_supra Posted November 27, 2008 Share Posted November 27, 2008 (edited) Grr, the car was basically running fine at santapod last month until on the way home i accidentally left the ecu cover off and my passenger kicked the ground wire out for the ground on the fcd, meaning that it was running seriously rough and rich on the last stretch home. hadnt worked on the car for about 3 weeks, until i eventually sorted the ground out. Started the car up and it was hesitant at idle, so i soaked the plugs and the O2 sensor in lemon juice for a week as they all looked pretty black from the over fueling i had been suffering. (plugs had only done 500 miles). Fired the car up again and it was still hesitant, turns out another wire on the ecu had been slightly pulled out from the back of the plug. This solved the hesitation at idle just fine. So i took the car out for a drive and it was running fine, but when under load at around 3.5k rpm whilst accelerating a heavy missfire occurs. Its not like a hesitation, but a strong vibration, which although the revs will pull through, i am sufferening a strong performance loss and a drop in about 6 psi on the second turbo. I've checked the diagnostics port, and no fault codes have been stored (just a constant flashing.) I replaced my coil packs and coil pack clips recently due to a hesitation issue, which had been resolved. So basically what im asking for is some ideas, as to what this could be and what to check. Edit: I took the car out for a round trip of about 80 miles yesterday, keeping the car off boost. I checked the fuel gauge after the journey which i do quite often and it did seem to use a little bit more fuel than normal. Edited November 27, 2008 by miko_supra (see edit history) Quote Link to comment Share on other sites More sharing options...
miko_supra Posted November 27, 2008 Author Share Posted November 27, 2008 just did a quick calculation and it seems on that journey i got no better than 14mpg Quote Link to comment Share on other sites More sharing options...
Thorin Posted November 27, 2008 Share Posted November 27, 2008 Try new plugs. Quote Link to comment Share on other sites More sharing options...
miko_supra Posted November 27, 2008 Author Share Posted November 27, 2008 But would bad plugs cause it to run rich? Quote Link to comment Share on other sites More sharing options...
lui Posted November 27, 2008 Share Posted November 27, 2008 (edited) Spark Plugs, coil pack or coil pack clips are what I would be checking Edited November 27, 2008 by lui (see edit history) Quote Link to comment Share on other sites More sharing options...
miko_supra Posted November 27, 2008 Author Share Posted November 27, 2008 Spark Plugs, coil pack or coil pack clips are what I would be checking done it all recently, replaced the lot. But i ordered a new set of plugs. Quote Link to comment Share on other sites More sharing options...
D8MOA Posted November 27, 2008 Share Posted November 27, 2008 damaged anything when you removed the plugs? sounds like a problem i had on my old TT ended up being the VSV the open the valve for the 2nd turbo Quote Link to comment Share on other sites More sharing options...
miko_supra Posted November 27, 2008 Author Share Posted November 27, 2008 damaged anything when you removed the plugs? sounds like a problem i had on my old TT ended up being the VSV the open the valve for the 2nd turbo not that i know of, I really dont want this to be one of those expensive "buy this, try that" type diagnosis as i dont plan to have the car for much longer. Quote Link to comment Share on other sites More sharing options...
miko_supra Posted November 28, 2008 Author Share Posted November 28, 2008 Ok, my new plugs arrived today, all gapped and what not...but still the problem persists. I have a video that im uploading at the moment of the car running at idle Quote Link to comment Share on other sites More sharing options...
miko_supra Posted November 28, 2008 Author Share Posted November 28, 2008 http://uk.youtube.com/watch?v=wBUDatElBsg Quote Link to comment Share on other sites More sharing options...
ManwithSupra Posted November 28, 2008 Share Posted November 28, 2008 Im just throwing an idea here but have you checked your ignitor pack?? Quote Link to comment Share on other sites More sharing options...
miko_supra Posted November 28, 2008 Author Share Posted November 28, 2008 Im just throwing an idea here but have you checked your ignitor pack?? not yet, thanks for that. Ok, i pulled the fuel pump out and checked the connections on that...all ok. I've now just pulled the engine loom out and started checking that, as said before this was were my problems first started. I noticed one of the wires going into the back of the plug for the main ecu was loose and i could easily pull it out. So just in the process of mending that at the moment. Quote Link to comment Share on other sites More sharing options...
miko_supra Posted November 28, 2008 Author Share Posted November 28, 2008 Put the loom back together again, seems that the idle issue has gone away but the vibrations at full boost still occurs. Im gonna try running it in ttc mode next time i get a chance to see if its an issue with the sequential system. Quote Link to comment Share on other sites More sharing options...
miko_supra Posted December 1, 2008 Author Share Posted December 1, 2008 Just tried ttc and the problem is exsactly the same. Could it be a dud ecu? Quote Link to comment Share on other sites More sharing options...
jim_supra Posted December 1, 2008 Share Posted December 1, 2008 Just tried ttc and the problem is exsactly the same. Could it be a dud ecu? It wouldn't hurt to try a different ecu. when I had problems with mine, I tried everything to sort it, then sent it away to someone else to have a look at it who then came back with a list as long as my arm of things that it needed. After the first few things they tried didn't work I asked to get it back and decided to change the ecu just on the off-chance it was that. It cured the problem completely. I could have saved myself a fortune as the ecu and autobox ecu cost £50 Quote Link to comment Share on other sites More sharing options...
miko_supra Posted December 1, 2008 Author Share Posted December 1, 2008 It wouldn't hurt to try a different ecu. when I had problems with mine, I tried everything to sort it, then sent it away to someone else to have a look at it who then came back with a list as long as my arm of things that it needed. After the first few things they tried didn't work I asked to get it back and decided to change the ecu just on the off-chance it was that. It cured the problem completely. I could have saved myself a fortune as the ecu and autobox ecu cost £50 ok thanks Jim, i've put a request up in the wanted section. Quote Link to comment Share on other sites More sharing options...
miko_supra Posted December 1, 2008 Author Share Posted December 1, 2008 doing some more tests and what not, and i dont know why anyone likes their car in ttc mode. Its horrible, big old drony exhaust, lag and then it just wheel spins all the time. Quote Link to comment Share on other sites More sharing options...
Steve Posted December 1, 2008 Share Posted December 1, 2008 doing some more tests and what not, and i dont know why anyone likes their car in ttc mode. Its horrible, big old drony exhaust, lag and then it just wheel spins all the time. Its quite nice when it has been mapped properly with an Emanage Quote Link to comment Share on other sites More sharing options...
miko_supra Posted December 18, 2008 Author Share Posted December 18, 2008 Just tried out a new ECU on the car. ECU worked fine, but the problem still persists. Looking at the boost gauge, the misfire occurs right at about 13psi (just under 1bar.) Im starting to think perhaps i have a dead coil pack, which would be like going round in circles as i changed them a few months back (with a second hand set) to get rid of a slight hesitation under full boost. Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted December 18, 2008 Share Posted December 18, 2008 What is the AFR reading when the miss occurs? could be way too rich or lean. Quote Link to comment Share on other sites More sharing options...
miko_supra Posted December 18, 2008 Author Share Posted December 18, 2008 What is the AFR reading when the miss occurs? could be way too rich or lean. I dont have an AFR gauge im afraid. I have wondered about the afr's though, perhaps too much fuel being sent through. May have to invest in one after xmas. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted December 18, 2008 Share Posted December 18, 2008 What plugs have you put in it? Quote Link to comment Share on other sites More sharing options...
miko_supra Posted December 18, 2008 Author Share Posted December 18, 2008 (edited) NGK - BCPR7ES gaped to 0.7mm Brand new and have gone through 2 sets of these with my current set up with no issues. Boost is set to run at 1.1bar with full decat Edited December 18, 2008 by miko_supra (see edit history) Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted December 18, 2008 Share Posted December 18, 2008 I dont have an AFR gauge im afraid. I have wondered about the afr's though, perhaps too much fuel being sent through. May have to invest in one after xmas. I think that would be very wise, a wideband is also a good diagnosis tool. Quote Link to comment Share on other sites More sharing options...
miko_supra Posted December 18, 2008 Author Share Posted December 18, 2008 I also tried the car with the FCD disconnected to see if it was an issue with that, but the problem was the same and as the boost only reached 13psi i didn't hit the stock fuel cut. Quote Link to comment Share on other sites More sharing options...
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