Bad Idle and Misfiring

[supraguy31]

Ok all, Here is one for you. We at a site called celicasupra.com do a few conversions from a 5mge to a 7mgte. Now with this conversion the problem we are having is the engine will start up pretty good in the morning while its cold, As soon as it warms up, It starts to pop like a small backfire from the Exhaust. Engine doesnt shake at all. Pops about every 3 to 4 Sounds but not always at that time.

Now, If you put it into Gear, Hold the Brake and slowly let off the clutch, The poping sounds gets pretty bad and it seems to be sluggish when you press the gas when at Idle.

We have checked the Crank timing mark, Cam timing marks, CPS timing, New wires and Plugs Cleaned out the ISC and checked the TPS . Even though we have done all this, If you put a timing light on it, The timing mark is bouncing about 5 to 7 Degrees on the crank.

Would anyone here be able to narrow this down for us. We have been working on this for about 2 weeks now and cant figure this out. Any help would be greatly Appreciated.

Could it be Knock Sensor, Bad ECU, Bad AFM???????
What the heck is a Code 11?

Robert Maynor

 

[suprra_girl]

code 11 = momentary interruption of power to ecu

it's too late for me to figure out the rest lol

 

[Supra Blues]

^What she said for code 11.

I had code 11 when I did a 7MGTE swap in my 87. Unfortunatly I never really found it. The code itself is not component specific and it takes time to narrow down if it is a short or component failure.

My symptoms were different however. When mine acted up, I just didn't get any spark at all. I ended up wrapping up the part of the wire harness that crosses the front of the engine just behind the cams. No more problems.

Your issues appears to be something different though.

Have you looked at the online TSRM to do some diagnostic work yet? Almost sounds like one of the coils is bad.

 

[supraguy31]

Well, Ive done a few Diagnostic on the ECU, I have 12 volts to B1, B2, and E1. From there, Its says try another ECU. I dont want to buy another one if there isnt anything wrong with this one. Im getting really good Spark, It Idles fine and all, Its just that when you give it gas, It want to Sputter and If you put the engine under a Load, I starts to Pop its ass of from the Muffler. Not for sure if a Knock sensor being bad will cause this.

Cant get the timing mark to stay still either. Jump the Diagnostic port, Use a Timing gun to set it and the Mark is bouncing around from 10 to 15 degrees.

Robert