blues

First thing when started it sounds like it is running on 5 cylinders but after 30 seconds or so it smooths out and runs fine. Has been doing this for several months now.

Now a new problem, when driving if you step on it lightly it misses and surges but if you stem down on it hard it is fine.

Due to the come and go nature of the problem I don't think it is plugs but I suppose it could be. I have seen posts at other sites mentioning it might be a ECU but not which one.

Any suggestions?

Buttercup

Does it always happen on every startup? Like if you were to turn off a warmed up car, wait a few minutes then turn it back on.

As for the light throttle, it seems to happen to my car only during the high idle cycle during warmup.

blues

NO, IT ONLY HAPPENS ON THE FIRST START UP IN THE MORNING AND THE FIRST START UP AFTER SITTING ALL DAY AT WORK. Once It warms up you can turn it off at the store or something and it is fine when you start it again.

VJ RC51

HAHAHAHAA i just had that problem, spent a few hundred $$$ and 3 weeks of car downtime trying to figure it out!!! Does it smoke a little bit also? Mine started running bad slowly after sitting for over 6hrs or overnight and would take 15mins or so of driving to clear up, then got slowly worse and worse. Its the fuel pump, ask around the forums (supraforums and here) for a stock soarer, supra, or any SC fuel pump for cheap and spend the 15mins it takes to change out, and your car will run beautiful again