Wierd WOT no shift issue???

[BARRACUDA1968]

Just got my motor back in along with a new Stage 3 trans. I've been babying the car for a while but after I re-torqued the heads Sat and had a few miles on the trans I decided to run it through the gears. As soon as I hit 5200 rpm the motor cut's out like it's hitting the rev limiter. Mine is set at 5700 in the SD2 chip. My logs look fine everywhere. Once the event happens my PL stops recording. No KR etc.

The only things I changed was Cometics to Felpro's and old trans to stage 3 Extreme Automatics. It feels like Bo's TTA with weak valve springs but it ran fine before I pulled it all the way to 5600 rpm so that can't be it.

Any guess's?????

It won't shift from 1 to 2 at WOT, or 2 to 3 etc otherwise shifts great under normal driving.

 

[ITSAV6]

TV cable set correctly? Might get more response in tranny sect.

 

[BARRACUDA1968]

I questioned that myself so I called Lonnie and he said I have it set right. The tranny will want to shift at 5200 to 5500 rpm at WOT according to him so evidently I can't build enough rpm to hit the shift point. The shitty part of the whole deal is I got my a$$ ate by a 2003 Cobra when we went hammer down for the first time. Now I got to hear a wins a win for the next year.

I'll bring up another factor that I doubt has anything to do with my issue but my trans got built with the wrong speedo gear so my MPH is showing 7 mph to high. Probably not a factor but I wasn't sure if it was fooling the SD2 chip or something?

 

[TT/Ameasap]

Check all the easy stuff:
Plug gap
Wires
Grounds
Coil pack
Are the plugs new?
The way i found my problem was heavier weight oil. Lifters collapsing with too much sp.
Keep it simple

 

[BARRACUDA1968]

I had 2 buddies helping put the car back together so you know how that goes. I checked a few things today over lunch. Positive batt cable was loose at the battery and the stud in the alternator was loose. When I get more time I'll go around everything and check for beer break and forget incidents.

Plugs are the same I used last year. I saw no need to change them with 1000 miles. I have an extra coil set up that came with the car. Not sure if it's any good or not??? I'm sure I'll find something simple.

It acts just like your car did Bo but with zero KR plus my PL log quits as soon as it acts up which is why I went and checked my battery and alternator. Volt's on the PL are perfect until the incident then I lose my log so?????

I just can't imagine having enough spring pressure last year and not enough now.

 

[BARRACUDA1968]

Went back and looked at the grounds, I took them all loose and looked for an issue, Found nothing. Re gapped plugs at 28. Went back though valve lash and set them at .006. OHM'd wires.

I still have the same issue. 5200 rpm and I hit what feels like a rev limiter. I put the car in 2nd gear and ran it up to 5200 rpm with basically no boost and the same thing happened. Bap-Bap-Bap and I let up and it runs great.

What next?

Could the SD2 rev limiter be messing with me? I have it set at 5700 rpm. I have no KR when it cuts out etc. I lose the datalogger when it cuts out as well. The log looks good until 5200 rpm and then the motor cuts out and the log quits.

 

[whitehot1]

Went back and looked at the grounds, I took them all loose and looked for an issue, Found nothing. Re gapped plugs at 28. Went back though valve lash and set them at .006. OHM'd wires.

I still have the same issue. 5200 rpm and I hit what feels like a rev limiter. I put the car in 2nd gear and ran it up to 5200 rpm with basically no boost and the same thing happened. Bap-Bap-Bap and I let up and it runs great.

What next?

Could the SD2 rev limiter be messing with me? I have it set at 5700 rpm. I have no KR when it cuts out etc. I lose the datalogger when it cuts out as well. The log looks good until 5200 rpm and then the motor cuts out and the log quits.

Can you turn the rev limiter off to see if it is causing the problem?

 

[whitehot1]

It won't shift from 1 to 2 at WOT, or 2 to 3 etc otherwise shifts great under normal driving.

What did Lonnie say was causing this?

 

[DR BOOST]

Went back and looked at the grounds, I took them all loose and looked for an issue, Found nothing. Re gapped plugs at 28. Went back though valve lash and set them at .006. OHM'd wires.

I still have the same issue. 5200 rpm and I hit what feels like a rev limiter. I put the car in 2nd gear and ran it up to 5200 rpm with basically no boost and the same thing happened. Bap-Bap-Bap and I let up and it runs great.

What next?

Could the SD2 rev limiter be messing with me? I have it set at 5700 rpm. I have no KR when it cuts out etc. I lose the datalogger when it cuts out as well. The log looks good until 5200 rpm and then the motor cuts out and the log quits.

set the valve lash to .006 ? are you running a solid roller?

 

[whitehot1]

Check out this thread. Post #37 was what cured his problem. Not saying you have the same problem but there are some good suggestions to look at for the problem you are experiencing in the thread.

http://turbobuick.com/threads/all-out-of-tricks-breaking-up-5300.187101/#post-1313173

 

[BEATAV8]

What plugs are you using? Non resistor type can cause the power logger to stop recording because they have more RFI which messes with the computer.

I would run the engine up to your desired engine speed at part throttle low boost, less than 5psi. Hold it in 2nd gear. If it cannot do this then it certainly will not run up properly at WOT. This exercise will help identify issues and will be easier on your motor and give you some data that's useful for tuning the VE table.

 

[turbocamino1]

you mentioned the SD2 possibly messing up...if you cant turn function off,maybe set it for 6000 and see if your issue that was at 5200 is now at 5500?

 

[Pronto]

If you have a tack handy you could set it up temporarily to confirm the rpms match the Powerlogger. I agree, raise the rev limit, see what happens.

 

[BEATAV8]

Also be aware that the SD2 can be programmed to cut you off if you overboost, but that's not likely unless you've been in there setting up those parameters specifically with that function in mind.

 

[BARRACUDA1968]

Can you turn the rev limiter off to see if it is causing the problem?

I'm not sure? I ran out of time last night to keep going on it. It's possible I suppose that the Rev Limiter setting of 5700 is too close to actual RPM and the ECM is getting ahead of itself??? It didn't do it last year though when it was set at 5600 rpm.

It won't shift from 1 to 2 at WOT, or 2 to 3 etc otherwise shifts great under normal driving.

What did Lonnie say was causing this?

Won't shift at WOT in any gear but shifts fine otherwise. Lonnie said it has nothing to do with the tranny I'm just not getting enough rpm to hit the shift pressure at WOT.

set the valve lash to .006 ? are you running a solid roller?

I have the short travel comp 885's .004 to .006 is the correct lash setting according to Comps website.

Check out this thread. Post #37 was what cured his problem. Not saying you have the same problem but there are some good suggestions to look at for the problem you are experiencing in the thread.

http://turbobuick.com/threads/all-out-of-tricks-breaking-up-5300.187101/#post-1313173

I will check that out thank you.

What plugs are you using? Non resistor type can cause the power logger to stop recording because they have more RFI which messes with the computer.

I would run the engine up to your desired engine speed at part throttle low boost, less than 5psi. Hold it in 2nd gear. If it cannot do this then it certainly will not run up properly at WOT. This exercise will help identify issues and will be easier on your motor and give you some data that's useful for tuning the VE table.

Plugs are R5671A-9 currently gapped at .028 which worked fine last year motor wise but I did have trouble with PL interruption at WOT once in a while. Have resistor racing plugs on the way to give them a try.

I did run the motor up to 5200 rpm (VDO tach reading anyway) just like you said and it cut out (Bap Bap Bap) I didn't have my laptop so I didn't log anything. I was running out of time and went for a short cruise to see if I had made any progress which I didn't.

I thought I would post here before I start throwing parts at it and wasting a lot of time. All I did from last year to this year was pull motor, change head gaskets that were leaking oil, re install motor with new trans and go again. Then this problem showed up???? Since it's not trans related then what is it?

I had the timing cover off so I reset the cam sensor. I used the caspers tool like always.

I had the crank sensor off the motor but it looks fine and not interfering with balancer.

Other than that everything is plug and play.

 

[BARRACUDA1968]

Also be aware that the SD2 can be programmed to cut you off if you overboost, but that's not likely unless you've been in there setting up those parameters specifically with that function in mind.

I've never messed with those settings but that's what it feels like. It feels like a rev limiter, meaning it's a clean bap bap bap and not a break up pinging type of deal if that makes any sense.

If you have a tack handy you could set it up temporarily to confirm the rpms match the Powerlogger. I agree, raise the rev limit, see what happens.

I will raise the limit next time out. My tach reads 5200 ish and PL is reading 5400 ish. The limit is set at 5700 in the PL. I did notice last night when I did the slow run to 5200 rpm that my check engine light flashed when the motor cut out. Not sure if it was the shift light feature or a real event in the ecm?

Here's a screen shot of a log in 1st gear at a WOT. It cut out and never shifted until I let out of it. The PL stopped logging.

 

[Pronto]

Turn off the shift light to take that out of the equation.

 

[BARRACUDA1968]

Will do

 

[BEATAV8]

The resistor style plugs should cure the data logger interruption

 

[BEATAV8]

Also do you use RFI suppression plug wires? Like magnecores?

A straight up racing style wire without any RFI suppression could potentially cause computer problems too