I have an 87 Supra Turbo. The 7M-GTE was rebuilt about 950 miles ago, It ran great and idle was perfect. Just recently I found a coolant leak on the hose from the throttle body to the heater core??? any way I replaced the hose and put a new gasket on the upper part of the intake manifold. Now when I start the car idle goes to about 500 rpm and then dies. Any Ideas?
Idle problem
- Thread starter 1SLOMK3
- Start date
It's normal to have idle problems after a battery disconnect. It should normalize after ~15 minutes of run time.
Normal? I have disconnected the battery on my supra 10 times and on several customers supras and never had any idling issues after at all....
Devin LeBlanc;1698959 said:
Their cars weren't "supramania'd". I don't think it should take 15 minutes to relearn the idle speed position. Unless there is something wrong with the car.
What Nick and Devin said. There's an enormous amount of misconception on this site about ECU learned values and how they work. The OP's car clearly has other problems.
Chances are you created a leak somewhere when you removed the manifold either from a gasket not sealing or forgetting to put a vacuum line back on. Double check all your vac lines and make sure nothing like a wire is caught between the manifold and the lower intake. Also make sure you plugged all your connectors back in properly.
Devin LeBlanc;1698959 said:
Nick M;1698977 said:
jetjock;1699031 said:
Hmm…I’ve owned three Supras and worked on many others. None of them idled normal immediately after a battery disconnect. Some take longer than others. My current supra (91) doesn’t idle normal for 3-4 minutes. I must be doing something WAAAY wrong!
And, for the record, I know better than to make a statement like that. I officially open myself up to lashings in the town square....
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Ok, one thousand lashes to CajunKenny with a wet noodle.
I'm with Cy, check all your connectors and vacuum lines. For the heck of it check your codes, it might shed some light as to what's going on.
I'm with Cy, check all your connectors and vacuum lines. For the heck of it check your codes, it might shed some light as to what's going on.
Kenny: without getting into a lot of detail I'll make it simple: The closer learned values are to null, the closer they are to the default values used by the ECU after reset, the closer the engine will immediately run as it did prior to reset. That's how the car was when it left the factory and that's how it should be kept.
That makes sense, but consider that the learned values prior to the reset were not close to default, wouldn't that affect the first start up?jetjock;1699172 said:
There is a grand total of 16 bytes of stored data, and one of those bytes is used to tell the ECU that there is valid data in the other 15 bytes, so that is a total of 15 bytes for stored useful data. Some of those 15 bytes are used to store fault codes, there is even less learned! The target ISCV setting for idle with and w/o A/C is all that is saved. Also, target idle is a function of coolant temp, so if coolant is below 80C your idle will be high.
It's a ground. Which one...I can't tell from the picture; but, yes. It very well may be the problem.
Nice find!
Nice find!