Chad T

Hey Guys,

Recently I had my injectors cleaned and flowed and installed an 034 Motorsports intake manifold spacer. I also had to re-solder my intake air temp sensor as removing and installing the manifold broke the wires again.

The car starts fine in the morning but when I start it to leave work at lunch or go home it takes quite a bit of cranking to get her to catch and she will run rough for just a few seconds. After that everything is fine and dandy. No codes "4444" code is all I get when checking for faults. Just get the weirdness when she's sat for a few hours. Starts beautifully after sitting overnight though.

Any wild *** guesses as to what I might have disturbed when R&Ring the intake? I was thinking it could be a reference sensor but it starts right back up when hot.

TIA

Chad

yodasfro

Any different if you hold throttle all the way down?

Chad T

Not really. I did try that today.

yodasfro

fuel pump check valve?

ColoQuattro

If I give it throttle it has backfired through the intake and then started so don't do that.
I just have not had the stomach to work on another fuel pump issue. It doesn't look to hard in Bentley's compared to what I have had to do in the past as I think (no hope) that there is a access door and the tank does not have to come off the car.

jurq

similate your drive to work, then park her and pull the injectors, stick them into a container, then check to see if they leak any fuel. This type of leak would only really present itself after the car sits for a few hours.

HTH,
Jim

Chad T

Nothing like a drive home on friday to simulate a drive to work. ;-)

I really hope that's not it as I just had them tested, cleaned and flowed. None were leaking before or after the cleaning according to the test results.

Good possibility though as the car never had this particular quirk before. The weird thing is it seems to start up almost instantly in the morning. Even better than before the cleaning.

The only other thing I did was pull the fuel pump relay and turn the engine over to de-pressurize the system.

Chad T

I would think that would give me worse symptoms in the morning though.

jurq

If fuel pressure is down, then the check valve is leaking back to the fuel pump/tank. If fuel pressure is maintained for a few hours after shut down, then this is not likely your issue.

jurq

since they've been cleaned and flowed. For a warm start, the plugs are still wet from any fuel leaking out of the injectors, causing a long cranking period and initial rich-running symptoms. During a cold start, the plugs have likely dried somewhat and therefore have no issue starting.

Just my $0.02