This is for the tr pros only basic knowledge already has been applied

[wbzautocustomiz]

Ok this is a ongoing problem have already posted threads for the past 2 years just want to see if I can get some order to my madness; Car will idle fine drive fine until it gets around 3200rpm than it will pop, stutter back fire, etc. and CE light will flash as it acts up.
What should this do if not working right or if bad?
1)ign mod/cp? Of course the basics car wont run proper what else?
2) maf? When bad what are the problems that will occur?
3) Cam sensor? If bad only issue car wont start? please exclude comment on out of adjustment 180 deg.
4)ECM? if bad how to tell I have 4 total all bad?
5)Crank sensor? New and adjusted other than that what else?
6)TT Chip? if it goes thru the motions of operation of TT how to tell if bad? I have 3
7)TPS? If st to specs with a old/new how to know if bad?
8)ALL Grounds relocated, repaired relocted
9) Balancer bolt tight, no vac leaks detected
10)voltage always 13.2-14.4
11)FP good 1 to 1 with boost and upgraded pump and hotwire ADJ FPR. Help me please!!!!

 

[Razor]

3200 rpm free revving? Under load? Boost/no boost?

MAF could cause the issue. You can watch AF on your scanmaster.
Corrosion on ECM plugs could also cause this.

When check engine light flashes does it store a code?

 

[mygm]

bad head gasket, first basic 3 to check: what condition & color were the spark plugs, did you do a compression test? did you do a leak down test.

 

[wbzautocustomiz]

Razor- yes 3200 freely, yes under load, yes under boost if it lets me
AF sm readings 255 with 2 different mafs
no corrosion
MYGM- plugs look ok grayish/whiteish tried different gaps also
no compression test no leak down test as of now

I want to add that as problem happens in park or driving CE light will flash then radio, sm, etc will blink off as if key was turned off
And yes have checked to make sure batt cable isnt shorting out on header, etc

 

[turboclam]

Check grounds...back of passenger head and under turbo on front of block. Make sure chip and cal-pack are seated in the ECM correctly. Try a different ECM. Any moisture around ECM harness?

 

[mygm]

grayish / white: indicates lean, if every electronic is turning off and on indicates a bad short, did you check the battery cable that goes to the alternator, could unplug the alt may be shorting internally,

11)FP good 1 to 1 with boost and upgraded pump and hotwire ADJ FPR

^ power wire attaches at the back of the alt, and runs along your frame rail, may be chafed against metal

 

[Ed Valvo]

Flat cam lobe. Have you pulled the VC's off to see if all the the rockers move the same?

 

[wbzautocustomiz]

MYGM- I have to really think if I checked that have been doing so much to car can quite remember but thats a good thought it is a autozone alt
Yes all grounds are checked, cleaned, reterminated, relocated, added extras, etc on grounds. Chip seated (have 3 TT chips)and calpak also I do have a total of 3 ecms all do the same and new ECM ends were graphed in due to corrosion a while back but problem was there then and now. If calpak is bad can this cause problems if yes what?
I did leave out that car will not go to "batch or limp mode" when cam sensor unplugged when running will idle fine for over 30 min but if I drive under med-wot throttle car shuts off on its on plug cam sensor back in and starts right up

 

[Ed Valvo]

Local car same thing. We change ALL the sensors. Chased this for 2 years off and on. We then decided to pull the VC's and then we found mechanical issues. One rocker was abnormal in movement. Or more like lack of movement. It never made any irregular noises. We ended up pulling the cam and lifters and putting a new top end on the car. Car runs like a champ now.

 

[joey316g]

Check the valve springs. Make sure you dont have a broken coil on any of them.

 

[Greg Wentz]

I had a similar problem 15 yrs ago on my T-Type. It seems the ignition module was bad. The car would run fine under 3000 rpm, but anything over that in would bog down and take a nose dive in power.

 

[BEATAV8]

X2 on the flat cam lobe... also chased it on a local car for a long time, going after chips and MAFs and wiring before finally finding it was the cam.

The classic is #3 exhaust. That's the one that wipes out.

 

[timdesu2000]

I dont know that I qualify as a TR pro but I am a GM master tech. If you get a flashing CEL light and pop or cut out at the same time I would want to see what voltage is at the ECM battery and IGN feeds. Need to hook up a volt meter and check each one as you rev it up and see what the reading is when it acts up. If the voltage on one of the feeds is low trace the high resistance in the circuit. If you find the voltage is 15 or over unhook the alternator and see if your problem goes away. Too high can be as bad as too low. Most modules have internal protection and shut down if the voltage is too much. Can also voltage drop the grounds at the ECM if you dont find anything on the power feeds. Do have a schematic for the ECM? I can try to find a pin out if you need one.

 

[Ed Valvo]

On our car, the backfiring must have made a sensor go whacko. Can't remember which code it was. Here is a pic of the cam that was pulled. Lifter pic is above. This made no abnormal noise and ran fine until one day just started missing/popping under part throttle like yours.

 

[wbzautocustomiz]

No codes stored havent pulled vc's yet , going to check all feeds for voltage readings hi/low on wiring and yes I do have a schematic and even better I have over 500 pages in 2 binders that I call my TR bible I have bad weather so cant work on car til next weekend but I will do whatever I have to do to try to get to the bottom of it, and I just said pros since I have been thru all the basic stuff but all help is really thankful for from all you guys, keep it coming cause I will take all ideas for help. Thanks

 

[TurboBuRick]

A worn cam lobe will not make the ce light flash. For that matter you can rule out any mechanical issue.

Your problem has to be related to a sensor or electronic device that is failing or out of whack.

Did you ever get a ac delco module on the car?

 

[TurboBuRick]

I want to add that as problem happens in park or driving CE light will flash then radio, sm, etc will blink off as if key was turned off
And yes have checked to make sure batt cable isnt shorting out on header, etc

Another key piece of information. Check the wires on the starter. Check the negative cable at the block.

 

[wbzautocustomiz]

ordering module from nosgn, wires at starter seem to be good but ordering a caspers pos batt cable kit that reloctes fuse links all on monday to do it since I know I need it as far as ground goes have o gauge fram batt to factory spot on the block and 1 from batt to firewall and 1 to pass side inner fender

 

[TurboBuRick]

Post some pics of your battery cables and their terminal ends.

 

[Chuck Leeper]

Key switch?
Main harness [firewall], plug?