2GNT won't run, only firing on 2 & 3?

euroticcustoms · 12-07-2007, 10:10 AM

Hey guys, just ran across a 96 RS 5spd with 48K miles, psr, crank windows and manual locks. Cleanest interior i've seen on one of these cars. factory 16" alloys, new tires, new kenwood cd player, aftermarket taillights.

The guy is asking $1500...he said he bought the car not running...the guy he bought it from wanted $1500 but he picked it up for $1200. Said he pulled the head and had it checked...it was a little warped, had it resurfaced, new head gasket and timing belt. I guess they put it back together and it still won't run. He says he's got almost $1500 in the car.

Anyway, he says the car is only firing on the inside cylinders. The wiring to the coil has been cut and spliced back together for some reason...all connections were headshrinked and look good. I have 3 spare coils...also have a head with 96K and no bent valves. I told the guy I'd come back this evening with a coil and compression gauge and see if I could diagnose the problem, but I'm not really sure if I want to do that.

I was thinking that if I call and offer $1300 he'd probably take it, but if I find out what's wrong with it and get it running, he might not want to sell it and he definitely won't budge on price. I do know that it doesn't run. I also know the fuel pump is working, so that leaves timing, ignition, and ECU. I know these cars can be a bitch to time if you don't know what you're doing.

So, either the rednecks who put the head back on didn't get it in time, the coil is bad, the ecu, or some wiring problem? I don't know for a fact that the car isn't firing on 1 & 4, just what the guy told me.

Just wanted to get a 2nd opinion?

Thanks ahead of time.

Paul

silvreclips · 12-07-2007, 10:38 AM

I would first test to see which cylinders are firing and which aren't, just so you know for sure. I would test the coil pack. It that checks out then check out the wiring to see if it was put back together correctly. To test the wires, unhook the battery and unplug the ECU. Check the resistance between the coil pack plug and the wires at the ECU. That will tell you if there is a problem with the wiring. If everything checks out then replace the ECU.

Locke · 12-07-2007, 11:05 AM

Quote:

Originally Posted by silvreclips

I would first test to see which cylinders are firing and which aren't, just so you know for sure. I would test the coil pack. It that checks out then check out the wiring to see if it was put back together correctly. To test the wires, unhook the battery and unplug the ECU. Check the resistance between the coil pack plug and the wires at the ECU. That will tell you if there is a problem with the wiring. If everything checks out then replace the ECU.

Do as mentioned here ^^ except don't replace the ECU right away. You can check for a signal from the ECU to fire 1 & 4 by disconnecting the coil plug and checking for an alternating 12V signal (12V - 0V) between the centre terminal on the harness, and the one which would be nearest to the fire-wall - as installed - while cranking.

You can likewise check for an alternating signal from the CAS as well, as a failed CAS often prevents 2 cylinders from firing.

Then check this: Wire harness melted against EGR pipe

Then try an ECU replacement.

BigRand · 12-07-2007, 11:40 AM

Bring a multi meter, test his coil pack with the multimeter, if you don't find an alternator current on the leads that fire 1&4 or even 2&3...I would hook up your coil pack and check the leads before you try to start it up, and see if there is any difference at all. At least you'll know if anything changed before he does.

turboglenn · 12-13-2007, 12:09 PM

I'd say if you're wanting to buy it. Don't go over there and fix it. Just tell him that it could be so many differrent things that you won't be able to tell with out taking it home and getting it apart to working on/testing each part individually. BUT, do go over and do a compression check, it if is good buy it. if there's any problems with compression cancel the deal. This is something that you should be able to fix easy by either replacing the CAM sensor, the coil ( there's no ignitor used on teh 420a as far as i know ) or the only other thing would be the ECU or the wiring in between.

If the cost of any of those parts + the price of the car are in the area of what you're willing to spend, then i say do it. But that's just me, if i know i can fix it i'd rather buy it broken cheap and then fix it. Rather than to fix it for the guy for free and then have the price go up if not stay firmly where it was.