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No, and KeithG is right. Posted by Justin VanAbrahams [Email]  (#32) [Profile/Gallery]
(more from Justin VanAbrahams) on Wed, 28 Feb 2001 17:41:03
In Reply to: Is it normal?, scottp, Wed, 28 Feb 2001 15:45:18 Members do not see ads below this line. - Help Keep This Site Online - Signup |
KeithG is right. There is no provision for "high idle" on Bosch LH Jetronic injection. *Some* fuel injected cars have an initial high idle to get oil to the head as quickly as possible, but LH is relatively stupid and doesn't account for anything like that. And, cars that do will idle a few hundred RPM high (like 200 to 3000) and certainly not *double* normal idle. Good examples would be my '87 Accord and '90 Taurus SHO. Fuel injected Saabs don't do this - new ones or old ones.
The usual causes for this would be a faulty air mass meter or a faulty idle control valve. During the warmup period, the AMM is mostly responsible for keeping idle under control until the O2 sensor is fully warmed up. High or fluctuating idle can be caused by an AMM which is not measuring correctly. The AIC is a stepper motor, and as they age they can become "lazy" and not properly adjust themselves to keep idle at the right speed.
Beyond all this, your '89 Turbo should have LH Jetronic 2.4 injection. v2.4 (as opposed to the earlier v2.2) was updated to keep cold idle more reliable. Specifically, the ECU memorizes the last position of the idle control valve and automatically resets it to that position when the car is restarted, rather than relearning its position as it did with 2.2. The pro of this is that it *should* virtually eliminate anomalous idle problems. The con is that it is very adept at covering up other idle-related problems, like vacuum leaks, failing AMMs, or O2 sensors.
As Keith said, I would take it back and have him fix whatever he previously fixed, but do it right this time. My suspicion, from experience, is that it may be a bad AIC - I had very similar symptoms on my '90 SPG when I replaced the 8 year old AIC with a *brand new one*. Took the new one back, got another new one, and the problem is all better. Alternatively, you may have a vacuum leak somewhere that, once warmed up, the system is able to compensate for, but can't do so until the O2 sensor is warmed up.
-Justin
, Wed, 28 Feb 2001 17:41:03 <-- Viewing This Message
, Wed, 28 Feb 2001 15:47:40
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