Help, ignition breakup at 3300

[dees75z]

Ok,
Don't really know where to start............... New coil new module(86-87), resisted wire eliminated and hotwire to alt. is done. Took car to the Dyno, ign breaking up know matter where I gap the plugs at(22-30). Also tried running a one step colder plug(NGK ur5) and still did the same thing with it gapped to 30. Car seemed like it was going to make pretty good power 170whp and 240trq(at 15-16 psi) at 3000 then broke up real bad. Not sure if it is an ign problem or not but I went ahead and ordered a set of ur6 plugs and was going to try and gap them to 33 and see what happens. Was trying to have the car ready for a local event this weekend but doesn't look like I am going to make it at this rate. AFR's seemed pretty lean to me, but it didn't like anything below 12.2 On strait 93.

Any help would be appreciated even though I know you die hard hot air guys don't like what I did with the car:wink:

Thanks,
Dee

 

[burnout]

I had the same problem with my ignition but it was more like a back fire. I found a loose pin on the factory module connector. I was using the jumper tho. Where did you order your hot wire kit?

Dave

 

[dees75z]

It was kindof like a backfire. What was weird is I turned the boost down and it ran worse..........???????Didn't really understand that.

 

[dees75z]

the more boost the better it does , if u let it go to 25 + psi of boost it wont break up and a/f never changes but if let it stay in a safe zone at 20 psi it will break up at 3300 rpm . less boost breaks up faster more boost less breakup and higher rpms ! any help !

 

[flippy1974]

isnt anybody going to try and help ! i guess nobody on here knows anything !

 

[BRAD_PADGETT]

isnt anybody going to try and help ! i guess nobody on here knows anything !

The above comment is really not necessary. The problem could be in many different places. I suspect coil module first. Plugs gapped at 33 are good to go. The next suspect may be a bad cam shaft or a bad crank sensor. You really need a scan tool. Good Luck. Brad

 

[dees75z]

The above comment is really not necessary. The problem could be in many different places. I suspect coil module first. Plugs gapped at 33 are good to go. The next suspect may be a bad cam shaft or a bad crank sensor. You really need a scan tool. Good Luck. Brad

well we have a coil and module .i have dfi computer and its not showing any codes , so how eles would we know if the crank sensor is bad since we are not using the factory computer , i think were going to try and get a cam noy for sure what size yet .
thanks for the reply .

 

[flippy1974]

The above comment is really not necessary. The problem could be in many different places. I suspect coil module first. Plugs gapped at 33 are good to go. The next suspect may be a bad cam shaft or a bad crank sensor. You really need a scan tool. Good Luck. Brad

i just want to get alittle help to try figure this thing out , i thought that comment might get a response and it did thanks for the help

 

[BRAD_PADGETT]

i just want to get alittle help to try figure this thing out , i thought that comment might get a response and it did thanks for the help

I smell a bad MAF sensor. A weak MAF will not throw a SES code but will screw things up. Run the car at idle and tap on the MAF with s screwdriver. Listen for any change in idle. Also, get some carb cleaner and spray every vacuum line and listen for any idle change. Post you results. Talk to you after the NCAA game. Brad

 

[flippy1974]

I smell a bad MAF sensor. A weak MAF will not throw a SES code but will screw things up. Run the car at idle and tap on the MAF with s screwdriver. Listen for any change in idle. Also, get some carb cleaner and spray every vacuum line and listen for any idle change. Post you results. Talk to you after the NCAA game. Brad

were not running a maf , he got aggravated last night and we started tearing it down to do some port work on the heads and put new springs and get a cam and lifters . what cam do u recommend for him .i dont know anything about these cars or much about turbos my car is a 383 with a lot of n/x on it thats my power adder of choice . the most i have messed with a turbo is on my truck and there not much to adding a bigger turbo to it since it all mechanical

 

[BRAD_PADGETT]

were not running a maf , he got aggravated last night and we started tearing it down to do some port work on the heads and put new springs and get a cam and lifters . what cam do u recommend for him .i dont know anything about these cars or much about turbos my car is a 383 with a lot of n/x on it thats my power adder of choice . the most i have messed with a turbo is on my truck and there not much to adding a bigger turbo to it since it all mechanical

Cam- I run stock. Do some homework on better cams. Port the heads and intake at the same time. The car will not run right without a MAF or use the new SD chip from TT. Good luck. Brad

 

[Boostnitup]

I suspect camshaft

I stay out of the diagnosis issues 99.998% of the time because we have guys who do this as a "career" and I do it as a hobby.

This is the symptoms of a rounded off camshaft lobe. (experienced it)

Lose a lobe?

 

[Jerryl]

isnt anybody going to try and help ! i guess nobody on here knows anything !

NICE first post!
Welcome aboard.

 

[Jerryl]

well we have a coil and module .i have dfi computer and its not showing any codes , so how eles would we know if the crank sensor is bad since we are not using the factory computer , i think were going to try and get a cam noy for sure what size yet .
thanks for the reply .

Ok, let me guess this;
You have an IC conversion, aftermarket ECM, running SD, changed coil and ign module, and the car breaks up at low boost around 3300 rpm, but high boost at same RPM it's fine?

It is NEVER easy to walk the road less traveled. :wink:

 

[dees75z]

Ok, let me guess this;
You have an IC conversion, aftermarket ECM, running SD, changed coil and ign module, and the car breaks up at low boost around 3300 rpm, but high boost at same RPM it's fine?

It is NEVER easy to walk the road less traveled. :wink:

No it breaks up at 3300 at high boost too, just not as bad.



Well, thats fine.

If anyone is interested in engine, tranny, and converter it is officially for sale. Shoot me a pm or email at dees75z@yahoo.com

dee

 

[TurboBuRick]

More then likley its your crank or cam sensor.

Try unpluging the cam sensor while the car is running and take it for a ride. See if the miss goes away.

Don't worrie about the ce light. A cam sensor code will be set.

 

[Jerryl]

No it breaks up at 3300 at high boost too, just not as bad.

Well, thats fine.
If anyone is interested in engine, tranny, and converter it is officially for sale. Shoot me a pm or email at dees75z@yahoo.com

dee

Dee,
So you figured this out, or just pulled the motor?

 

[dees75z]

Dee,
So you figured this out, or just pulled the motor?

Just going to pull the engine, trans and wiring harness. It is all for sale if you or anyone else is interested. Let me know.

dee