Of course, there's no awesome forums like this site for my DD Ford escort. Anyways... I can't figure this car out. It's an '87 pony(Plain jane) with a 1.9l CFI and a 4-speed manual. The car only has 43,000 original miles on it.
Now for the issue I can't figure out. The car cuts out really bad when under 1/4-1/2 throttle loads. I actually sold the car 2 years ago because I got tired of figuring it out. LOL! Now I bought it back with the same problem but with alot of new parts. New parts include... All new sensors (all of them), new fuel pump, fuel pressure regulator, fuel filter, Re-manned distributor, new TFI module, New ignition coil, new plugs and wires, new cap and rotor.
The car runs great when it's cold (closed loop mode for the computer). But as soon as it gets warmed up (open loop) then all hell breaks out. I can let off the gas and get it to run smooth but it's tricky. The only thing that hasn't been changed is the exhaust is still original, the fuel injector, and the alternator.
Anyone got some suggestions? I'd like to drive my blazer everyday... But this things get 39mpg running like poo....

 

is the check engine light on? Have you pulled the codes?
Fuel Injection Technical Library » How To Run a Self-Test

Have you checked the egr.. could be it's running open due to crud in the pintle {valve} and I bet the mpg increased when it started running bad.

directions on how to clean an egr.
https://blazerforum.com/forum/articl...leaning-40424/

It may also be that the pipe from your exhaust manifold is either plugged or broken. I'd guess broken if it's running that bad.

 

Yea, I'm not sure on the check engine light. The guy I bought it of of put a cluster with a tach in it. And that cluster doesn't have the light in it. But I'm going to pull the EGR apart this weekend and see what I can find. I just figured it might be something computer related since it's fine until the engine warms up. I'm thinking the cat might be bad too from it running like this for so long before I got it. The car does stink pretty bad. I guess at least I know it won't leave me stranded. LOL!

 

Really.. pull the codes. Look at the connector on the site I linked. I'll bet the check engine is on, and it's got stored codes. Never saw a non-ignition drivability problem on EECIV not store one, and if there's one stored it will point you right at it. The system is simpler than OBD II but works well

A small bulb connected to STO and 12 v + IS a check engine light.
Fuel Injection Technical Library » How To Run a Self-Test

 

pettyfog is the guy to talk to in regards to fords, that's for sure! I'd take his word as Gospel.