Idle wierdness? How is the SVO supposed to act, idle wise, on startup?

[pstocker]

I am not sure if my 85 SVO is supposed to act this way or not when I start it up cold or not. When I start it in the morning, it starts up and the idle immediately jumps up to about 2000 to 2100 RPM. It will hang out there for minutes and eventually slow down a little, but unless I tap the gas, it hangs high like that, then after tapping the gas, it drops back down to normal after about 20 seconds. It will stay like this till the engine is shut down and completely cooled off, then repeat.

Is this normal? Will this change any with the LA3 swap? I have heard it is supposed to smooth things out a bit. Thanks, -Phil

[Ken Potter]

Search TPS.

[dagenham]

My '84 does the same exact thing. I figure it is a cold idle feature just like having a choke on a carb'd engine.
Have you ever started it up and just drove off while it is still cold?? Mine does not run near as good if I try that.

[pstocker]

My '84 does the same exact thing. I figure it is a cold idle feature just like having a choke on a carb'd engine.
Have you ever started it up and just drove off while it is still cold?? Mine does not run near as good if I try that.

I will try it tomorrow. I have other issues as we'll like a stutter under almost full to full boost. I can feel the timing being pulled from it so I know something isn't right. Even when I run 93 octane, it feels like it is falling flat at only 12-15psi boost! I have checked for vacuum / boost leaks, especially at the intercooler and cannot find any.

[Erics SVO]

Try cleaning the IAC, it can also do this as well as no/low idle for cold startup.

[pstocker]

I have tried cleaning the iac, as well as another IAC, same thing to the letter. I will try to measure the TPS and adjust it this weekend.

Thank again...

[Bruce]

Get some high quality octain booster and try again. The lack of octain will cause weird things under boost! I disco'ed my knock sensor and it ran great but I got carried away and blew a head gasket too. Now my KS is back on-most of the time anyway!

[SchoolBoy]

Two things, check your base idle speed first then your tps as directed here....http://www.svoca.com/forum/showthread.php?t=11 When thats done, check your voltage at the battery when its running fast. If you don't see 14.2 or less than 14.0 your not charging right. My svo had a hunting high idle, tested voltage and it was only putting out 13.6, turned out the voltage reg was bad.

[BrianO]

it's supposed to do that.. it eventually comes down or if you tap the pedal to encourage step down. mine never goes down all the way, but once I start driving and stop again it's at normal idle the rest of the time.

[GAboySVO]

The ECU does have a cold warm up routine and will rev at initial startup and eventually decline as the engine temp rises.

Having to blip the throttle is most likely a throttle body linkage issue and blipping the throttle helps to overcome the inertia to the return spring with the momentum of the plate movement.

[svono50]

Do another search on ECT, they do go bad and make the EEC think the engine is always extremely cold and run a little 'weird'. Pretty easy to check, too. Good luck with your diagnosis.