what now?

[munkee]

I still haven't found whats causing the problem on my 90 mtx. After replacing the front head and the cam sensor last weekend, the backfire is gone but the engine still shakes, misses, and my coolant gauge still doesn't work. I have switched to motorcraft plugs and wires and I am positive that they are gapped and routed correctly and the brand new timing belt is also on correctly. The cps is gapped correctly and I am not getting any fault codes. I am going to be replacing the rod bearings this weekend but I don't think that has anything to do with it. I don't really notice a knock and no oil pressure light but the motor has 210,000 on it and the previous owner wasn't too good with oil changes. I have looked through the wiring and didn't find anything amiss but my temp gauge isn't working even though the gauge and the sender is fine. I am wondering if maybe something happened to a wiring harness. Has anyone had a problem before that could shed some light on this? I could definitely use some ideas if you have any. It really sounds like its missing due to a timing problem but I have gone over everything timing related. Thanks for all of the previous help, hopefully I can get it fixed this weekend.

 

[Mr Anonymous]

Have you checked your cats for blockage?

 

[munkee]

I haven't checked the cats specifically but I did unbolt the y-pipe from the manifolds and there wasn't a change. Well it was earshatteringly loud but the engine was still shaking and missing. Just a shot in the dark, but can a bad alternator cause this problem, or contribute? I went out to move the car tonight and the battery was dead.

 

[mustangdude]

are my based out of missoula MT currently? I dont think I could help you with anythigng unless you need someone to hand you tools but I owuld like to meet other showners and trade info on cars and such

 

[munkee]

mustangdude, I live in south dakota right now. shrug Can't wait for the day I can move back to missoula. It's been four years since I have gone snowboarding. I do make a couple of trips a year to visit though so maybe we can meet up sometime.

 

[mustangdude]

well anytime your in missoula just post and tell me and perhaps we can shoot up to snowbowl or chat about cars

 

[SHOfun 93]

is the bucking on startup? It might be a cam sensor not knowing which plugs to fire when. shrug

 

[munkee]

Well, the engine shakes at idle (kind of throbs like a race engine with serious amounts of torque) and it lubs like it has a race cam in it. If I hold the rpms at about 1700 the engine doesn't shake anymore and it misses every half second or so.
I replaced the rod bearings tonight and spent about 3 hours going over the wiring. The ONLY thing I found amiss was the wire for the oil pressure sender wasn't snapped on all the way and of course that didn't fix the problem. I was test driving it after I finished with the bearings and I no more than got on the road and was about to shift into second and the tach dropped and the engine died. WTF? That would point to the cps right? It is brand new, no leaky water pump or anything and I know the gap was correct. The car wouldn't start again so I left it until I can do something with it tommorrow.