One crazy problem, possibly ignition related.

[PanZero]

Hello guys! My DSM is having a crazy problem that nobody so far was able to solve. It's fine when I drive normally, but when I use more engine power for a certain period of time (like hillclimbing, or just generally "having fun" driving) it starts failing, the tach goes crazy too.

My mechanic told me it's cutting the ignition, for some reason, so far he wasn't able to fix it. After a while driving very slowly (sometimes I can't even go past 1500RPM when that happens), like when I get to the plains after the hillclimb, it goes back to normal. It makes no sense.

Anybody got any idea what it could be? Thanks in advance.

 

[pitbull419]

Have you verified your timing?

 

[Wil_Own]

Check your connections on you Cam sensor and all, I had the same problem and one of the wires right against the plug was broken off couldn't see it till you really looked hard.

 

[shockey1013]

+1 on checking all your connections. I would grab every connection and just make sure they are secured. My car does this every once in awhile and its because the Ignition Power Transistor plug wiggles a bit lose. The car falls on its face and the tack goes crazy, sometimes the car even back fires. I would check that connector first. Its the wide connector that is mounted right behind the fuel rail, to the left of the coil packs. Hope this helps.

 

[WES_393]

Check your Ignition Control Module (aka PTU). It's the black box mounted on the intake manifold behind the fuel rail. Just look for a large rectangular wiring connector. The crazy tach and loss of power is a huge sign that the ICM is failing or has a poor connection; It plays a huge role in the ignition system. Since the problem happens after extended periods of high engine load (which equals advanced timing), it's possible that the ICM is overheating and malfunctioning.

Most auto parts store have an ICM tester, but have no idea how to hook up the ICM from our cars (they use vehicle specific connectors). So you'd have to find a pinout chart in order to have them test it. So I'd check/clean the connector and see if that makes a difference. If not, try swapping on a know working ISC.

 

[luv2rallye]

+1 Power transistor probably has a temperature failure. You can try verifying it by heating it with a heat gun or hairdryer while testing: http://www.dsmtuners.com/forums/articles-electrical-wiring/229419-how-test-power-transistors.html

 

[AWDPetmitsu]

Did you ever get this resolved? I think I have the same problem. Here's my thread:

http://www.dsmtuners.com/forums/mai...15mins-driving-struggles-restart-then-ok.html

I'm thinking I have a faulty CAS. I ordered one and am waiting for it to get here.

 

[PanZero]

Sorry it took so long to reply. My mechanic tested the power transistor but that wasn't it. He ordered a new CAS but they sent him a wrong one twice now. I'll reply back as soon as I get an update. Since it takes SO FREACKING LONG for those CAS to arrive here in Brazil, any other suggestions are very welcome for us to try in the mean time.

 

[luv2rallye]

Make sure your mechanic tested the power transistor (aka ignition control module) while heating it with a heat gun or hairdryer. In fact you should try heating it while the engine is running to see effect.