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Low Speed Hot Stall

386 Views 2 Replies 2 Participants Last post by  Weather Man
Stalled yesterday on the Parkway coming out of a tollbooth, right at the merge, which was a bit terrifying. Most of the instrument lights came on (can’t recall which), and the car started right back up. We had been driving for 50 miles or so with a full tank of premium plus a bottle of Techron.

A bit of history. My fiance purchased the car a month ago in an estate sale. The mechanic basically got the car running after it sitting for 3 years. It had intially started and run fine.
Progressively it got harder to cold start and would stall. I’d have to give it gas until about 80C or it would stall. I also noticed it wouldn’t idle at 750 when the coolant gauge was under 42F; it would be closer to 500. It also stalled at low speeds with no pressure on the accelerator. The rpms and oil pressure would drop off, and she’d die. No dash lights would come on. This also happened more and more frequently.

I replaced the fuel filter yesterday. Not Bosch as I figure I’m going to need to do this again soon. Still needed to keep on the throttle until it warmed up. Ran great at all speeds until it stalled at the toll booth, it continued to do this at stop signs for the rest of the drive.

Here’s what I know:
Airflow plate moves freely when engine is off. It does not hesitate at the bottom when released.

Need to cycle the pump a few times and add starter fluid when cold, I’ll keep the throttle open until it fires, then release and lay on it a bit until the engine warms up. It does not crank for more than a second before firing.

Battery and alternator are both ok

During warm up, the engine speed increases by appx 100 rpm around 60C with a set throttle position

Does not lose power or stall when going up inclines

Seems a little sluggish in acceleration, but I am not familiar enough with this car to know

Does not stall when coasting and rpm is up. This is at normal driving speed

Stalls when slowing down, around full or rolling stop, oil pressure and rpms fall off

On the docket is: check fuel pump relay, check cold start valve, and thermo-time switch. Is there anything glaring I am missing?

Also going to do an oil flush and fill as it’s probably good after an initial Techron dose, right?

I do not currently have a cis gauge, but will see if I can get my hands on one.
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Update - air sensor plate offers resistance after cycling fuel pump.
The rpm increase is around 40-45 C by about 250 rpm.
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