Completed a 7mGTE JDM engine swap in my 87 Supra turbo, but have ignition firing issues. We installed 550 cc RC's (soldered RC connectors) and the Lexus AFM (Fabricated the custom Air Screw as recommended).We also retorqued head to 85 lbs, with ARP Head bolts.After initial richness and black smoke issues, pulled out new NGK iridiums and replaced with platinums.This cleared up the smoke. Performed coolant system pressure leak down and also averaged 160-165 lbs compression in all cylinders and they even flushed out the entire engine fuel management with a stand alone Snap-On system.They ruled out HG problems.Now after weeks of troubleshooting, the mechanics thought a coilpack issue, due to misfire.Swapped that with the same results. Engine starts right up without the starter injector even connected (idles close to 1000 though).What else to check? Anybody been there?
2,4,6 Missfire
- Thread starter 87fullKaminari
- Start date
87fullKaminari;1418858 said:
Not really much to elaborate on, you are most likely pulling in unmetered air from somewhere.
Or your afr is way wacky.
Are RC's high impedence or low impedence? If they're low impedence check the resistor pack for a good connection.
Check the turbocharger lower hose. It is by the oil filter. The hose can come off or split at the turbocharger housing. Unless you know to check for it it's hard to find.
Poodles;1419245 said:
Naaaa....codes are for pussys....everyone knows that the "beat your dick against the wall" method works better!
gaboonviper85;1419273 said:
hahhahah nice.
I love when people diagnose problems like dumbass rednecks.
I done did that bob, but i seen the sparks from the plugs so I think the computer done blowed up. :sarcasm:
yeah check the codes, it will make life much more pleasant when you have an idea where to start.
orrr
Open oil cap, put 2 extra strength advil tablets in there and wash them down with a bottle of water.
let us know if that works.
4 coils that fire 2 plugs at the same time in wasted spark setup. 1/6 2/5 3/4, so no way in hell for it to missfire on those 3....
First things first, check your codes.
As mentioned above, we have three coils on a waste spark system; so the misfire on 2, 4, and 6 can't be a problem with the coil packs. The only thing that ties those cylinders together are the injectors. Our batch fire system fires injectors 1/3/5 and 2/4/6 together.
That said, you still need to check the codes and see what shows up. Troubleshooting an engine code beats chasing your tail by guessing what the problem is, and wasting time and money "fixing" things that weren't part of the problem.
As mentioned above, we have three coils on a waste spark system; so the misfire on 2, 4, and 6 can't be a problem with the coil packs. The only thing that ties those cylinders together are the injectors. Our batch fire system fires injectors 1/3/5 and 2/4/6 together.
That said, you still need to check the codes and see what shows up. Troubleshooting an engine code beats chasing your tail by guessing what the problem is, and wasting time and money "fixing" things that weren't part of the problem.
87fullKaminari;1419596 said:
You've got that backwards. You can have codes and no check engine light, not check engine light with no codes.
There aren't any codes. They've hooked it up to their scanners and machines and are trying to narrow it down to a mechanical issue. All the sensors checkout and the firing order all confirmed.They suggested that I send the injectors back to RC to be requalified since they were sitting around for a few years, and they think that they might be "leaking".?The other theory is how to compare the primary to the secondary voltage from the 3 coilpacks that is resultant from the ground loop followed for secondary spark which is actually delayed so that there is equal voltage to the shared plug. Is it really that scientific?
What I know is that they have stand alone diagnostic monitored test equipment for confirming injector and spark firing orders etc.,along with the newer stuff. They think it's too much fuel or it isn't fully igniting, but why 2,4,6 is the mystery, and I guess there isn't simply a code to confirm.
So, try running it with the TCCS again. Perhaps this wacky stand alone machine they're using hasn't been properly set up for the waste spark system in use on the 7M. Which could cause one ignition event from each coil to not occur, I suppose...
BTW, is this you, or a "we", or a "they" that we are talking about? You started with "we" now it's "they".
BTW, is this you, or a "we", or a "they" that we are talking about? You started with "we" now it's "they".