Struggling after startup

[Renee_1632]

1632 starts with no problem, but for the first 5 or so seconds of depressing the gas pedal in either R or D, the car struggles to move and moves jerkily, then moves smoothly. It's only an issue after several hours of sitting and always fixes itself after a few seconds. Do I need a new fuel pump? Or is something else wrong?

[DMCMW Dave]

More likely something to do with the warmup regulator. It's either gone out of spec or the vacuum hoses are not hooked up correctly.

[Jonathan]

You have an automatic, right Renee? Do you have any maintenance history on your shift computer governor? Is it the original one or has it ever been replaced?

[Renee_1632]

You have an automatic, right Renee? Do you have any maintenance history on your shift computer governor? Is it the original one or has it ever been replaced?

I'll have to give Danny a call, but I'm pretty sure the PO had it replaced.

And Dave, what exactly does the warm up regulator do? It's probably old...I think it's still original.

[DMCMW Dave]

And Dave, what exactly does the warm up regulator do? It's probably old...I think it's still original.

Gives a richer fuel mixture on a cold engine, and gives more fuel when you hit the gas (all when cold only). Once the engine warms up none of this is needed and the enrichment functions are normally cut out of the circuit. If it's not working properly, the engine will have kind of a fall-on-its-face operation until it warms up a bit. In your climate that may only take a minute.

Cold = not running for at least a few hours. Regulators don't often fail on a car that's driven, more often after years of sitting and getting gummed up. But it can happen.

[Renee_1632]

Cold = not running for at least a few hours. Regulators don't often fail on a car that's driven, more often after years of sitting and getting gummed up. But it can happen.

Hmm. That's still plausible I think. It's my DD, and the PO had it as a weekend car, but the first owner locked it away for years.

[jfirios]

I am having a similar problem, though I am not sure it has to do with a hot start system or anything. I just had all this work done on the car and I know there is a ton of carbon buildup in the engine that I have to kick out. Driving it a lot to blow it all out now that I have all new injectors and the stage 1 exhaust done. The problem i am having is it is stalling a lot now especially when there is a bigger draw on the engine as when the ac is on, and that sometimes it feels like it is about to stall and the car revs itself up to keep it from stalling. I am hoping that it is something that will work itself out once everything is cleaned out of the engine, but not sure, what do you guys think?

[WelmoedJ]

The fuel system of cars that sat for a long time usually is cleaned before use.
However the small filter inside the connection to the fuel line (onder the big banjo) also usually is overlooked.
The same may go for the small filters for each of the chambers in the fuel distributor's piston cylinder may get clogged.

It may have been "solved" by turning the mixture screw to deliver a richer mixture.
A richer mixture often causes an almost starve situation when starting to drive off after a cold start, but letting the car warm up will decrease that effect and only show if accelerating fast while not fully warmed up.

[Renee_1632]

Thanks for the advice everyone...where is the warm up regulator? Is it difficult/expensive to replace?

[WelmoedJ]

Driver's side valve cover.
Why replace if cleaning and repair is easy?

[David T]

It could be the CPR (aka warm-up regulator) but I would also check all of the vacuum plumbing. There are several things going on during the warm-up cycle and a lot of them are affected by vacuum. The other side of the vacuum issue is vacuum leaks. They reduce the effectiveness of the control systems and cause a lean mixture which in many cases people try to compensate for by tweaking the mixture screw richer. Verify that the mechanical and vacuum advance systems are working.
David Teitelbaum