Rough start after not driving for a couple days

[3point2]

Something that has only been fairly recent, after not driving the car for a couple days, the motor starts up with some coughs/sputters before settling in on idle.

I typically have to back one car out to get the p car out of the driveway, and then swap them around. In the time i back it out turn the car off, then turn it back on to drive off after parking the other car, the coughing/sputtering doesnt happen.

So it only happens when left for a while.

Do the injectors possibly need a clean?

Car is an 84' Carrera

[pors1968]

it might be the check valve of fuel pump.

[JAR0023]

I had a completely unrelated car do this and it ended up being a leaking injector. -J

[3point2]

Thanks for the replies.. will have to get it checked out.

I took a short vid of a start up this morning after leaving it overnight. Morning was quite cool

https://www.youtube.com/watch?v=SKySLIT-j24

[Chuck.H]

Sounds like something may be causing the fuel pressure to drop, either a leaking injector, or leaking fuel pressure regulator or dampner (the things at the front ends of the fuel rails) or a check valve in the fuel pump.

But first verify this is your problem by getting a fuel pressure gauge (at harbor freight) and see how fast your fuel pressure drops. It 'will' drop after a few days, which is normal, but it shouldn't drop because of leak. If it drops due to a leak of one of those devices above, then it will leak into the intake manifold and cause a very rich condition when restarted.

Chuck.H
'89 TurboLookTarga, 369k miles

[3point2]

Thanks Chuck, could this potentially explain why the car stalls on occasion when cold with the rich mixture? Or am I way off?

[ManniB]

Originally Posted by 3point2

Something that has only been fairly recent, after not driving the car for a couple days, the motor starts up with some coughs/sputters before settling in on idle.

I typically have to back one car out to get the p car out of the driveway, and then swap them around. In the time i back it out turn the car off, then turn it back on to drive off after parking the other car, the coughing/sputtering doesnt happen.

So it only happens when left for a while.

Do the injectors possibly need a clean?

Car is an 84' Carrera

You don't disclose your location. Is it possible that outside temeratures have dropped where you live? Maybe the WUR is the reason? You might want to check your control pressure.

- Manfred

[stlrj]

Originally Posted by 3point2

Thanks Chuck, could this potentially explain why the car stalls on occasion when cold with the rich mixture? Or am I way off?

A rich mixture and loss of residual fuel pressure are two different issues and should be treated as such. It is possible that both issues are present, making diagnosis difficult, confusing and complicated.

[3point2]

I have had the stall issue looked at and has been greatly improved but not totally cured. The ICV was replaced, AFM checked and is good, CO is ok, idle micro switch is ok, base idle has been set properly. Just wondered if this possible issue is linked at all

[Chuck.H]

A fuel pressure gauge will tell you a lot - once the engine shuts down it should hold fuel pressure for a while, like 30 minutes and then slowly drop. BTW, if the fuel pressure regulator diaphram is torn, it WILL cause a rich mixture because the fuel will get sucked into the manifold via the vacuum line. These are easy to test by putting a vacuum test hand pump (ala mitivac) on the diaphram and seeing they hold vacuum.

Chuck.H
'89 TurboLookTarga, 369k miles

[tom1975]

Check the O2 relay
81 SC Oxygen Sensor Relay

[stlrj]

Originally Posted by tom1975

Check the O2 relay
81 SC Oxygen Sensor Relay

Not applicable for an 84 Carrera.