ESL

Tonight on my way home I was accelerating at wide open throttle in third to pass a car. When I got to 4000 rpm the car hesitated, the turbos emitted a sound which I can only describe as a belching sound and the check engine light flashed on and off about 5 - 10 times then stayed on. I tried it again with the same result - hesitation, strange sound and flashing CEL. I do not have a scanner so I can't tell you what codes are causing the CEL.
Does anyone know what the cause is?
What is a good, relatively inexpensive scanner I can use to reset the CEL and read the codes?
Thanks in advance,
Eric

UserA

Bad Diverter Valve me thinks. Will the CEL go off after a while?

ESL

Just happened tonight so not yet. I just had the oil changed in the car. Could they have damaged the diverter valves or just coincidence? Do bad diverters throw a CEL?
Thanks for the help!

Felix

You really need to get the codes read - we can speculate till the cows come home.

993MAN

My money is on an intercooler hose coming loose. This exact same thing happened to me a while ago and it was the hose on the LHS of the I/C.
My CEL came on as well but as soon as I refitted the hose on the side of the road it went out.
Check them anyway.
Cheers

AC/911's

Me too, all new hoses,top & bottom,you should hear air leaks under acceleration.

ESL

Well, the CEL went out. I will have my mechanic check the hoses this week. How can I check them myself?

Mike J

Open the hood, and check the connections to the intercooler. On each side of the intercooler (drive and passenger) on the bottom of the IC you will see about a 3" diameter rubber hose with a hose clamp connected to the Intercooler. That hose should be nice and firmly attached to the IC, not slipped off or partially off. The hoses are also prone to splitting on the ends, so check that too. Check both the left and right hoses. The left hose is harder to see, the right one is really obvious.

Its possible they have also blown off the top of the turbos (since that hose runs from the outlet of the turbo to the inlet on the intercooler), but the connection to the IC is the more likely suspect.

The CEL might have gone out if the hose is slightly loose, and it resealed if the pushed with lots of pressure, so take the car out and drive it hard, get the boost to 0.8bar, and see if it happens again. If it does not, then its not the hoses, but the diverter. I think the ECU will keep memory of any thrown codes, so if you read the codes (or your mechanic can), it will help diagnose the issue.

Cheers,

Mike

Cheers,

Mike

ca993twin

The two hoses are fitted between the turbo outlets (under the car) and the intercoolers (up on top). The usual scenario is that the hoses will "pop off" on the top, and will tear on the bottom. If your 1996 hasn't been retrofitted, get the 1997-style hoses with the orange ends for the top. Get some Breeze constant torque clamps and use them instead... a total pain to fit them on the bottom, easy on the top.

993MAN

^^^^
Most things on a TT are a pain to fit or get to.