Running Rough

[mwake83]

I have an 88 Ranger with a 2.9l. The engine recently started running rough intermittently at idle and while accelerating. It will do this for about 15 seconds and then usually run fine for a few minutes. It feels like the engine is not getting enough fuel and the engine rpms drop to about 400 then bounce back up. Runs like this when cold and warm. Checked fuel pressure, it is at 30psi while running, jumps to 38psi when sputtering. Pulled codes 22 and 43. No smoke out of exhaust. I have replaced fuel filter and pump, 02 sensor, map sensor, tps, tfi, and engine coolant sensor. Checked for vacuum leaks and have not found any. Any suggestions would be much appreciated. Thanks.

 

[mwake83]

Update: After running for a while and replacing tps and map sensors again with some donor parts I had I was able to get rid of codes 22 and 43. Gotta love getting parts that dont work from the parts store. Now I have a code 41 so I am going to replace the new o2 sensor next. Maybe I can go 3 for 3 with Autozone...

 

[kimcrwbr1]

Are you resetting the computer and erasing the memory before running the codes. You need to every time you clean/change a sensor.

 

[cavedweller]

Thinking on what you have given,symptom-wise,nothing concrete to offer yet,.....besides the IAC valve(idle air control),cleaning OR replacing it.... Parts-wise starting to really LOVE NAPA ,everyone else seems to pale in comparison .....

 

[mwake83]

I have not reset the computer yet. What is the process for doing this?

 

[06wing]

I just got through fighting similar symptoms on my '87. After replacing multiple items, ended up being EGR pressure sensor. Unhooked negative battery cable to reset while I changed out fuel filter and now is running ALOT better. Put a full tank of the good stuff and some Seafoam and gonna see how she does.

 

[mwake83]

Does the 88 2.9l have an EGR pressure sensor? If so where is it located. I know this engine doesn't have an egr valve.

 

[det107]

I have not reset the computer yet. What is the process for doing this?

......Really simple......
>Disconnect battery @ negative cable & wait about 10-20 minutes.
>Re-install cable.
>Computer should reset when started