I know this is the sub forum for MKIII's but it's still a 7M. Anyway, I swapped a 7M into my MKII and I have had a hell of a lot of headaches, mainly being injectors. At first I thought that maybe my ign switched power was shorting to the negative side of the injectors, then I thought maybe they were all shorted out (fat chance but whatever) so I switched over to 1992 injectors/plugs, still power to both sides of the plug! I de-loomed and unwrapped the whole harness yesterday and there are no shorts at all, so I was like, "Fine whatever, I'll check the TCCS." And of course the white/blue, white/red, and white injector wires all have power being fed to them from the TCCS!! What gives? What have I got wired wrong?
7M-GE wiring problem.
- Thread starter Master_Spazez
- Start date
Your checking for power with the clips unplugged and they have 12v on both sides?
Whats the problem not fuel?
Whats the problem not fuel?
I was, then I cut a wire I was unsure about from the start (10ga blk/red wire on the B1 conn that I thought I needed 12v constant) then I just had power from the harness side and not the TCCS. But now I'm getting no spark and I'm not sure if the injectors are being opened since there is still a lot of pressure in the fuel line.
For the swap you just wire up the body plugs. None of that matters for the ecu other than switched ign. Do you have batt, mrel, and b+ hooked up at the c1 plug by the alternator?
I have both B+'s hooked up, M-REL, 12v switched, and batt all hooked up. The injectors will not open and I'm still getting power out of the injector pins (pins 4, 8, and 9 on the 10 pin plug) on both my 1992 and 1988 TCCS.
Do you have any codes?
92 and 88 have 2 different ecus that are not interchangeable.
Are you using gray plug or yellow plug?
92 and 88 have 2 different ecus that are not interchangeable.
Are you using gray plug or yellow plug?
Yellow plug (however I used both since I looked up the pinouts and they were the same just the '92 had some added stuff where the '88 was blank). Haven't checked codes. What codes would I be looking for anyway?
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So, I re-wired my 1992 harness (figured it would work better on my '92 engine anyway) to where it was completely plug and play (so I hoped), but won't you know it it still doesn't start. I'm 1400% sure my wiring is perfect so I'm not asking about that, however I went to check my trouble codes to see if there was something physically wrong stopping it from starting, however the CEL just stayed lit when I jumped the connector! What does this mean, my TCCS is bad? It would definitely explain as to why I'm getting power from where I should have ground!
Is it possible for the injector driver to go bad? I get spark at the right times, just no fuel.
Nevermind, got it started. But it runs absolutely terrible, it'll idle for a few seconds but if I open the taps all the way it dies almost as fast as it starts. If I plug the AFM into the one on the body harness, it will idle, but I suspect only out of a strange loophole (the MKII AFM controls the fuel pump in a way). If it wasn't for that I'd say it was mechanical.
Is it possible for the injector driver to go bad? I get spark at the right times, just no fuel.
Nevermind, got it started. But it runs absolutely terrible, it'll idle for a few seconds but if I open the taps all the way it dies almost as fast as it starts. If I plug the AFM into the one on the body harness, it will idle, but I suspect only out of a strange loophole (the MKII AFM controls the fuel pump in a way). If it wasn't for that I'd say it was mechanical.
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Timing is good, haven't checked with a gun but base timing is at 10 degrees BDTC. Haven't thought to check the TPS since it was never removed, I'll do that tomorrow. Also the knock sensor had some crazy ass spaghetti wiring job so I'll shorten the wire up some and check the sensor itself while I'm at it.
ign timing should be set with the timing light to 10*.
cam crank timing should be at 0 and the notches matching the other notches.
cam crank timing should be at 0 and the notches matching the other notches.
You know, I could never get it to set DEAD ON 0 degrees, even with my 5M I'd always get like 10 or 5. Sometimes 15 but it never affected it the way this problem is. It wont rev past what I'd imagine is 4k rpm (no tach hooked up yet), takes forever to get there, and it has absolutely NO power.
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The injectors all get 12V when the key is turned on from the EFI relay. The ECU just grounds them out. The AFM actually acts as a switch for the Fuel Pump Relay. Turns it on and off.