My 1991 350 TPI with 130k miles was running just fine and then i noticed a sudden tone change in the car. I looked at my gauges and they were all fine but when i went to pull out of the bank, the engine acted like it was misfiring on a couple of cylinders. I got it home and checked the wires and changed the plugs to no avail. The car still idles kinda rough, but the misfire is most noticeable under the slightest acceleration or load (going uphill).

I don't know if this is the ignition module, the pickup coil, or something else spark related or if it is the Coolant Temperature Sensor. I don't think it is the CTS but someone on another post said that it was. I haven't changed the fuel filter, but i really dont think that is the problem...Like i said it was running just fine and it just suddenly changed while i was idling.

Any help would be greatly appreciated as i am ready to put a new motor in and i need to get this fixed asap.
Thanks,
Brandon

 

Check to make sure your MAP sensor plug is seated properly and the vaccuum hose to it is intact. Take a resistance reading on your cts and verify proper resitance for ambient temps. No codes? Run the car at night and look for arcing near the coil, plug wires, and plugs. Get back with us on those quick tests.

 

Well,
I replaced the MAP sensor and the ignition module as well as the coil. Right after i replace all of those, the car seemed to run BETTER, not like it did, but it didn't act like the misfire was as bad. Then today i went out to install the bracket on the coil and the car ran like **** again. I dunno what the deal is. I don't have an ohmeter or multimeter yet to test those sensors, but i should soon. I just dont understand why it would act up. Oh yeah i checked for codes and found none. One guy said that he had the same problem and found that one of his injector was nearly dead.
I have a new set of 30lb injectors for my new engine. Should i pop them in and see if there is a difference?