AA717driver

Anyone replace theirs? Mine is screwing up the idle after being warmed up and then stopping (coming off an interstate ramp to a stop). You can hear the fan come on, the idle pops up to near 1000 rpms and, eventually, the CEL comes on.

This started after the IMS/clutch replacement engine drop. My Indy found a split vacuum hose and he thought that cured it.

Ideas?

TC

Barn996

Be sure to search for a rebuild for the air pump done by the infamous KK. His step by step repair/rebuild was very complete.

AA717driver

Ill do that, barn. Thanks!

TC

RickMiller

Give it a shot. I did it, but it only extended it's useful life by a few months. It may have already been too far gone. You'll see - it's fairly easy to get out. I think I got my new one for $270 at Pelican.

R

fpb111

What year?

AA717driver

'04 and Pelican has them for $280. It just kind of sits up there in front--looks really easy to get to. I almost think it's a trap.

TC

Ahsai

If your pump is running and it's quiet, why do you want to replace it? Also, what are the codes that tripped the CEL? The surge to 1000 rpm sounds like vacuum leak when the pump and the changeover valve is activated. The changeover valve when activated lets vacuum flow to the SAI one way valve at the exhast side, which should not affect intake. However, if the changeover and/or tube is leaking, air can suck back to the intake.

Kalashnikov

Most likely you got P0491 or P0492 or both.

It is either the pumping or the diverter valves.

spruden

I did the KrazyK rebuild on mine in the fall. It's a piece of cake and the SAI Pump is a very simple little device. If the pump is running and moving air, without the bearings making a racket, then the pump is likely ok...there's just not much to it.

Seems like further investigation is needed - I don't think a failing pump would impact idle that drastically. It could be part of the solution for sure, but appears that there may be a second vacuum leak or related failure.

AA717driver

Code P0507 "Idle air control system higher than expected".

Like I said, you can hear the fan kick on and the revs fluctuate once you come to a stop. I'm not at all convinced it's a fan problem. It seems like it's something requesting the idle to kick up after harder driving when it's not necessary.

Off to the Indy when I get a chance.

Thanks all!

TC

Ahsai

P0507 could be due to air leak https://rennlist.com/forums/996-foru...cel-p0507.html

which is consistent with air leak in the SAI vacuum control.

AA717driver

When I had a similar problem right after the engine pull, my Indy found a cracked vacuum line. Maybe another one went...

Thanks!

TC

Ahsai

Quite possible. The code is not complaining about the SAI pump for sure.

sjg1138

Replacing all the vacuum lines with modern tubing is a great way to eliminate gremlins. Not a very difficult job either. The original lines get brittle and crack and the cracks are so small there is no visible clue that they are leaking.

TSMacNeil

Get some carb cleaner and spray around some vacuum lines, when the idle rpm increases you've found your vacuum leak.