After warmed up, rough idling, and stalls

1990 FORD E-SERIES VAN

27,500 MILES • 7.5L • V8 • 2WD • AUTOMATIC

CCOWDERY

MEMBER
1 POST

It starts fine but wants to stall after approximately 5 minutes.
The engine actually does stumble and stall after approximately 20 to 50 miles driving. re-starts after 15 minutes or so.
I have already replaced ignition coil, ignition module, fuel tank filter and screen, inline fuel filter.

Mar 30, 2022 at 2:33 AM

KASEKENNY

✓Experienced Mechanic
18,907 POSTS

Sounds like you may have a vacuum leak and that is causing all these issues.

However, let's start with these guides that will help with this exact issue:

https://www.2carpros.com/articles/evap-system-code-repair

https://www.2carpros.com/articles/smog-test-inspection-information

Next, we need to check for vacuum leaks and see if we can find any.

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

If there are no leaks, then we need to check for codes and find out if we have any which will point us in the right direction. Here is a guide that helps with this:

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Again, no codes, then we need to check fuel pressure when the engine warms up.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Lastly, if we find nothing with all this then I suspect you have a faulty o2 sensor causing the PCM to improperly adjust the fuel.

https://www.2carpros.com/articles/how-to-test-an-oxygen-sensor-02-sensor

https://www.2carpros.com/articles/how-to-replace-an-oxygen-sensor

Let's run through all this info and see what we turn up.

Thanks

Apr 1, 2022 at 2:53 AM

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