Posted this on another forum and wanted to put it on here too.

Alright from the top car started running real rough and missing with loss of power and hard to start. My I know nothing about the opti on the car plus the cap was broken so I just decided to replace the opti. Also replaced recently both O2's, plugs and wires. Start the car after opti change and takes a second or two longer to fire up than "normal". Everything was fine so I went for a test drive.

Under normal acceleration I can feel it surging and at 2k there is a very noticeable vibration from the motor. At WOT there is some popping and more surging and no vibration.

Get the car home and its now idling at 1200-1300 rpm in park. Check for a arcing light show and all is good. I hooked it up to datamaster and I would post the info but I don't know how. I don't want to just throw parts at this so any help is appreciated. My TPS% is .8 at idle with ~1V and 4.3 at 2K with ~1.10V.

 

The closed throttle TPS voltage should be less than 0.90V. If I read what you posted correctly, you are seeing approx 1V at idle, and the throttle position is indicated as 0.8%. That is not correct. Make sure your blades are closing all the way. If they are closed all the way, you may need to slot the TPS sensor so it can be adjusted to the correct voltage.

To check the voltage at positions other than closed throttle, with the engine OFF, hook up the volt meter and watch the reading as you slowly rotate the blades from fully closed (look for a reading between 0.20 and 0.90V fully closed) to fully open. The voltage shoudll increase smoothly with no spikes or dropouts, with WOT voltage reaching about 4V higher than the closed throttle reading. WOT voltage should not exceed 4.90V or you could get another code.

Is it possible you have a plug wired burned on the headers? Are you sure you got the plug wires in the correct order on the Opti? Is it possible you did not get the splined drive shaft on the Opti indexed correctly in the cam sprocket?

What brand Opti did you buy? Did you open the case and Loc-Tite the rotor screws before installing it?

 

I bought this opti
http://shop.advanceautoparts.com/web...1013276926____

I know its not a Delphi but I thought I would try it because It is a brand new unit not a rebuilt core with a lifetime warranty.

I did not open it up and loc-tite the rotor screw. Its a Vented style opti motor is a 96 sorry forgot to put that in my original post. Checked the plug wires and they are all in proper order and not burned on the headers. Cleaned and checked the TPS and its now idling normal.

It was doing this same stuff before the opti change could it be a failing coil or ICM?

 

You really should put the fact that your car has a 96 engine into your signature, so people can provide you with accurate responses to your questions.

 

Updated my signature.

 

If you have a DataMaster log, upload it to an FTP site, and post the link.

 

DataMaster Log

http://www.mediafire.com/?f7xrg53na2he74g

 

Went through checked and cleaned all the grounds and connections also cleaned MAF and TB. Checked the coil and it shows proper Ohm value. Check the throttle cable for proper tension and its good. Checked the opti harness and it had a slightly higher ohm value on the ground than what Shoebox's site shows. Check for vacuum leaks and could not find any. Will recheck proper Plug order when it cools down. Just took it around the block and it popping and missing really bad now.

 

I would double check and make sure you have the opti indexed correctly..Like Fred said..

 

Since he told us he has a 96 engine, with a vented Opti, it's not likely that it is indexed incorrectly. Putting the dowel pin in the wrong hole would put it so far out of time it's unlikely it would even start.

 

TPS volts are too high at closed throttle, but I assume this log was run BEFORE you somehow cleaned the TPS sensor.

Idle speed is too high, probably as a result of the TPS problem.

MAP looks OK

MAF flow is too high, but that's the result of the elevated idle RPM.

What was the ambient air temp when you ran the log? Inlet air temp is over 140*F. Seems high, unless you have 100* ambients.

System voltage looks a bit on the low side at 12.5V.

Some spots of knock retard, but that's just the result of blipping the throttle.

The PCM is pulling a bit of fuel (6.3%) on the left bank of the engine, and not pulling anything on the right side.

Run a log with the TPS fixed. And simply letting it idle and playing with the throttle is not going to provide a lot of useful data. Run the log from a cold start so it's in open loop. Let it warm up at idle until it goes into closed loop. Then actually drive it.

 

Alright it is now idling correctly I ran a new log like you said to from cold start open loop to closed loop then a quick drive. Coming out of my subdivision it ran great but when I opened it up on the Hwy she was stumbling and popping again still with a vibration at 2K.

Ambient temp yesterday was 95* with a heat index of 105* also I checked my alternator and it is outputting 14.16 V

http://www.mediafire.com/file/f76f71...av/7-25-11.uni

Thanks for all your help so far Fred I really appreciate it!

 

Check the plug wires again.....you have a bad one some where. I'd bet a whole nickel on it....

 

Alright I got the idle down some more and ran some new logs

From start up Normal driving
http://www.mediafire.com/file/qfo9t2...k/7-27-11a.uni

More WOT More popping and missing
http://www.mediafire.com/file/7hg1nt...c/7-27-11c.uni

 

I have triple checked but I will check again