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Ironmike, ASE Master Tech, L1
Category: Car
Satisfied Customers: 3385
Experience:  30 years GM certified, Ford certified
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99 eclipse: 2 weeks ago I did a cylinder head R&R..2.0 non-turbo..miss

Customer Question

2 weeks ago I did a cylinder head R&R on a 99 eclipse 2.0 non-turbo. now the customer says it dies in reverse. I found that it does not die but it does in fact have a single cylinder miss while in reverse AND MOVING SLOWLY. does not begin under load (stall) but once it starts to miss it will continue no matter how much throttle you give it. while it is acting up it can at times come and go with nothing changing, nothing at all. each time it has done this it goes away before my boss can get over to investigate. it is unpredictable as to when it will occur. the MIL is on with only a code for the downstream O2 heater (it had this before we did the head).
there is no wiring out of place, I am anal about this and have triple checked with an open mind. there is nothing in the vicinity of any moving parts including the axles, shift cable or linkage, engine mounts etc. I see absolutely no physical reason for this. the only thing I have come up with so far is that something in the tranny or the PCM is affecting the ignition system or one of the injectors. the new plugs show no signs of an ignition problem but then again it rarely occurs. (I dont have access to a 4 gas analyzer to see if it is fuel or ignition)
this car is all factory un-molested except for a "cold" air pipe and gauze type filter (it is a speed density car so no MAF).

any ideas at all?
Submitted: 8 years ago.
Category: Car
Expert:  Ironmike replied 8 years ago.
                      I found a tsb on making sure the replacement head gasket is correct to prevent engine knock. That is for engine replacement but I see other tsbs,s for spark or ping diagnosis. Did you clean the piston heads? One more thing, I saw a honda that had one cam off one tooth, it ran but lumpy. Never a bad thing to double check the valve timing.
Good luck Mike
Customer: replied 8 years ago.
head set was from the dealer. new T belt was installed with the marks lined up using a straight edge across the cam bolts. piston heads were in fact cleaned (normal practice). it feels like a single cylinder miss as it is rather sharp, not just low on power or sluggish
Expert:  Ironmike replied 8 years ago.
            If you know the cylinder sometimes it is easier to swap plugs, injectors or plug wires. I seen spark plugs or the boots on some ignition systems do this.
Expert:  Ironmike replied 8 years ago.
             I took a better look at the ignition system. I have seen these systems with misfire issues and the coils go bad and can lose one cylinder. I would ohm out the ignition wires first and look for arc tracts on the boots where they go into the head. Genreally it is 1k ohms per inch.
Customer: replied 8 years ago.
new wires were installed during the head job. on Friday afternoon I installed a new coil pack as the customer needed the car for the weekend. it did not act up all afternoon, that is until I went to back it out the door for the customer to get it.
Expert:  Ironmike replied 8 years ago.
           Sorry for the delay. We need to know what we are missing(fuel, spark) and what cylinder is misfiring. When we have issues like this at the dealer we have to duplicate the issue, they are getting tough on replacing parts that haven't failed(especially under warranty)
Customer: replied 8 years ago.
customer picked up the car on friday and hasn't been back since. if you dont mind i will put this on hold for now. i am hoping to get it back next week and try to narrow down which cyl. is the problem. I am also suspicious if this may be a problem with a trans solenoid pulling down either an injector or coil driver circuit.
Expert:  Ironmike replied 8 years ago.
          That's what I was thinking, a coil driver or injector driver in the pcm. Good luck    Mike