First I wanna say I have 1987 LTD Crown Victoria with a 5.0 (I know it's not a mustang but figured somebody would still have some insight). I've been dealing with a sputtering and jerking in my car. It does it whether it's idling, accelerating, or up to highway speed but it is definitely worse under load. It is an intermittent problem but tonight was the worst it's done it. Here's what I've replaced so far:
-Spark plugs
-Wires
-Cap
-Rotor
-Ignition Coil
-TPS sensor
-ICM on the Distributor
I have an aftermarket K&N air intake and dual exhaust with the downstream cats removed. EGR valve is unplugged and capped off. I have ran it this way for a long time with no issues and great performance. I also 'tested' the MAP sensor tonight. Started the car and disconnected the vacuum line with it running and the engine killed so I know it's not stuck open/closed. I ran a KOER test and the codes I received were DTC 31, DTC 94, & DTC 44 which all point to emissions I believe. (I should mention I had a TPS code that has gone away since I replaced it but the car is still running the same). My next go to would be the pick up coil in the distributor, vacuum leak, or a fuel issue. Here's the weird part; during the KOER test the vehicle did not sputter once and it ran completely fine. As soon as the test was complete it began sputtering/jerking again, so would that mean it's something ignition/electrical? My gut tells me to shotgun the pick up coil and look at the distributor. Any insight would be helpful. I've already thrown quite a few parts at it and figured I'd check here first before I keep replacing stuff.
-Spark plugs
-Wires
-Cap
-Rotor
-Ignition Coil
-TPS sensor
-ICM on the Distributor
I have an aftermarket K&N air intake and dual exhaust with the downstream cats removed. EGR valve is unplugged and capped off. I have ran it this way for a long time with no issues and great performance. I also 'tested' the MAP sensor tonight. Started the car and disconnected the vacuum line with it running and the engine killed so I know it's not stuck open/closed. I ran a KOER test and the codes I received were DTC 31, DTC 94, & DTC 44 which all point to emissions I believe. (I should mention I had a TPS code that has gone away since I replaced it but the car is still running the same). My next go to would be the pick up coil in the distributor, vacuum leak, or a fuel issue. Here's the weird part; during the KOER test the vehicle did not sputter once and it ran completely fine. As soon as the test was complete it began sputtering/jerking again, so would that mean it's something ignition/electrical? My gut tells me to shotgun the pick up coil and look at the distributor. Any insight would be helpful. I've already thrown quite a few parts at it and figured I'd check here first before I keep replacing stuff.