northdakota93z28

can i take off the cap without removing the water pump? i have a high rpm stumble (top of 3rd at 4000 rpm) and i have all good fuel stuff, pump, filter and injectors. so i have moved on to ignition, new coil, wires, plugs and now i want to check the opti, i just had a cap and rotor kit put on a year ago it mabey has 3000 miles on it! i am getting very frustrated and i have to figure the problem out. any help would be great!!

Green96Z

Nope, sadly you have to pull the WP to remove the opti. Maybe your stumble is due to an out of balance? Are you sure the front balancer is on right?

northdakota93z28

ya i have never messed with the balancer, could it be a knock sensor mabey pulling timing i read that in a diff thread. how could i even check that??

northdakota93z28

i forgot to say the high rpm stumble started after i got my headers.

95zsean

Are you sure you dont have a bad plug wire,the headers could be close enought to hurt the wire but not but not burn it off. Also check to see if the caps are on tight.

LearJet

+1 for plug wires

The Engineer

Not sure what your problem is, however, it "is not" the front damper. Again, LTs have a damper and not a balancer (LTs are internally balanced on the front of the crank). Furthermore, the factory damper isn't even keyed on the crank, therefore it can slip on the crank without causing an issue.

WD

northdakota93z28

i have ovcw, and they are all on good.

northdakota93z28

has this miss ever been a knock sensor??

The Engineer

The knock-sensor will not cause a miss. When knock occurs and the sensor responds, timing is retarded in the PCM. Performance is impaired, but no miss occurs as a result.

One common problem with LTs is for the Opti rotor screws to vibrate loose (I've see that many times). Not easy to check, but one of several things to check.

WD

northdakota93z28

can i data log a 93 obd1?

northdakota93z28

that would make a stumble?? it is not a miss it is a stumble.

northdakota93z28

my friend just downloaded tunercat for me and we are going to check some stuff out tonight, he has never done much with a lt1 but he knows tuning stuff, this is his car

http://video.google.com/videoplay?do...arch&plindex=0

Injuneer

You need a scanner (TTS DataMaster or FreeScan), not a tuning program. You need to find the problem before you can determine if it can be fixed by a tune, or if its a mechancial or electrical problem that needs to be repaired.

shoebox

I doubt that timing retard would even cause a stumble. The only thing you shoud perceive is a lack of power.