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Yesterday 1:35 pm

I had something odd happen to me last week where my van started sputtering out on idle after driving.

Did a fuel pressure test and on cold it would be 30psi and jump to 39 when I disconnected vacuum. As the engine got warmed up I kept seeing the fuel pressure die down all the way down to 25 even 23PSI. Also hearing the engine slowly jerking and bucking a bit more.

Is this a fuel pressure reg problem? Could it start to fail when the temps got hotter?

I recently had a block in my fuel system on the return line that shot my fuel pressure to 90PSI. Im guessing this could have damaged it. What do you guys think? If not that could it have damaged the fuel injectors?

Yesterday 1:43 pm

More likely a fuel pump laying down. There is a volume test described in the manual. Perform the test on a cold engine and repeat when the pressure has dropped. I don’t recall the values.

Yesterday 2:02 pm

The fuel pump is under a year old but it was working overtime when I had the blockage. Could it have been damaged that badly from the pressure?

Yesterday 2:22 pm

The pump might be losing power not just internally failing. The volume test should tell you.

Or, you could crimp the return from the regulator when the engine is cold and read the max pressure and record it. Get the van warmed up where the fuel pressure is dropping and crimp the return and see if you get identical fuel pressure. This method is less accurate.

You should probably put a volt meter across the two terminals when the engine is first started and record the voltage. Then measure again when the pressure drops.

A restriction on the suction side could also affect fuel pressure. You mention fuel system problems prior.

Yesterday 4:47 pm

Ok I'm going to check the upstream side of the circulation. Will start with volt meter though.Thank you for the advice

I find it odd that it would lose power. I drove it for two hours the day prior and had no issues on cold start and then running on highway. It was only when I got home. Idled for a bit. Put in reverse. Then stalled. Cranked again and started right up but felt like it wasn't getting enough fuel.

The day prior to that. I only had issues when it was warmed up as I mentioned.

So if it did lose pressure while I was driving it wasn't enough for me to notice. Maybe because the revs were high?

I have a new FPR coming in tomorrow. If I dont have to throw away my current one that'd be great but I was thinking it was the FPR not holding pressure when heated up.

Yesterday 6:18 pm

Hoping I’m wrong.