GSR Swap wont rev past 4k, tried alot of things.. help please

my current problem is basically limp mode. no codes right now.
is not revving above around 3500, and if you rev it dies out. does not sound right. it is like it is stumbling when running. idle sounds okay, but not normal.

have changed plugs and wires, tried another coil, a whole different distributor, and had the chip in the ecu checked. the car has been running fine for the past 6 months since the last time i had trouble, which turned out to be a leaking fpr. and fine before that for 3 months or so. i know it is not something wired wrong, or not wired up. tried pulling injector plugs and there doesn't seem to be a bad injector. but there is an exhaust leak, and the car is running so rich that it burned our eyes while trying to test them.

the last work done on the car by me was oil change a few weeks ago. also had some exhaust work done right after that, and they put in a new o2 bung, it is still intact and wired up.

replaced map and tps, map made it a hair better, and tps was worse. my tps is good. checked wire connections, and vaccuum lines. have not found anything loose or missing.

if anyone has any advice please help me out, car is 93 eg8 with chipped p28, yes just got chip checked and reburned. no difference.. no idea where to turn, MAYBE bad ecu? doubt it though, but anyone with advice please help.

and YES i've searched, but all the threads i've found have NO answers.. thanks!

 

EDIT: throwing code 21- Variable Valve Timing and Valve lift solenoid (VTEC solenoid)

But would that cause all this? Spark cut at 4k..?? Doubt it.

 

When does your VTEC engage in your tune? if it goes at 4k then yes it would cause you to cut out at 4k... just saying

 

Well, replaced solenoid. No difference. Chased the wires back under the dash to the ecu, found a short in the orange wires (vtec wires) soldered it up. CEL is now gone. But, bad news is car won't hardly start anymore. And if it does it dies a few seconds after.. i'm almost to the point of giving up

 

The timing on the distributor might be off as well as the timing belt
Although you cars turns on the fuel pressure might be low if it is on for more than 10 seconds, anything before that it can be your fuel pump. It can be going bad.

 

and your fuel FILTER could be bad as well....
i would first make sure that distributor is on right before messing with the fuel system.
Check your spark plugs and wires to see if they are covered in oil.

 

Dont rush the process and take your time. You must be over looking something. If i could i would take a look at it and fix it for free

 

I was thinking maybe timing, idk though.. not too sure about the fuel filter i dont think its bad as it's been running really rich when it actually did start. now it won't start at all. distributor is on right, checking fire order, etc.

Thanks for the advice, and motivation man

 

When the car turns over, try to feed it gas and see if it stays on.......if it does,then its a problem with your fuel system and not timing. If it doesn't then its obvious. Good luck, im going to keep checking up on this.
My boy has a single cam that would turn on and little by little the idle will drop and turn off.
It turned out to be it was off timing by a lot, The dude bought Greddy timing gear which wasnt for a single and it was slippin. so i hope you far from that type of trial and error.

 

Did you ever try to use a stock GSR ecu?....

 

no problem with fuel system. can't get ahold of a stock gsr ecu. codes are now all cleared, still does the same.. anyone have anymore advice.....thanks...

 

try an ground out the wire to ur tps to firewall i had same problem with my gsr swap after grounding the tps it worked fine let me kno if this helps

 

^ I will try that. No more codes, all codes are fixed, STILL won't hardly start. Took plugs out and put oil down cylinders over night, started today and it started up. New plugs tho, started up and idles at like 300, won't rev past 2k and if you rev it it dies instead of dropping back down to idle...pretty sure its not in limp mode as it won't even reach 2k rpm's

 

Just as a thought.....unplug the IACV electrical plug when car is warmed up and running. If idle doesn't change....then the IACV is bad.

Is this stuff a new swap or was it running fine and started doing this all the sudden?

P28....how is cold idle dealt with? Does it need/have Fast Idle Thermo Valve?

I'd like you to try a OBD1 P72 ECU and hook up knock sensor and IAB's so you have a virgin set up with no chip

Do you know what map has been put on it? What's been deleted?

 

The swaps been in for a year+ running fine. Last thing that happened with the motor was the fpr went out leaking gas into the intake. Replaced been fine ever since. Most recent thing done was the exhaust a few weeks ago. I'd like to try a p72, i hope to try one very soon..

The map is tuned on chrome, vtecs set at 5,100 2 step at 5,000. Not sure what's all been deleted..

not sure what the deal with the iacv is, unscrewed it, and started to car and let fuel pump prime to see what it does, it like blips (opens for a second then goes back) is this what it should do? It doesn't seem to open all the way.. when unplugged it idles at 1,000-1,500. When plugged it idles at around 200, but when you rev it it dies, then the iacv starts making a humming noise..

I'm out of ideas, not sure why the iacv hums like that though..

 

Also it throws no codes, but when I put in the jumper wire it's a solid cel. But theres no codes with the jumper wire out, i heard a solid cel means bad ecu BUT there's no cel when the jumpers wire in it. not sure how it works, but i thought if a jumper wires in it and theres no cel's the light would go off not stay on? Not sure though.

 

Get a Virgin P72 like the dude said and your IACV shouldnt be doing any noises...if it is then it could be clogged.

 

Will do.. so no noises should be coming from iacv..

 

With car at running tempature.....and unplugging the IACV....the idle should drop to roughly 450-500rpm (really low) and it should "normally" idle (with everything plugged in and fine) around 750-900rpms

What are you "UnScrewing" on the IACV???

IACV "may" be dirty. Take it off the IM and clean it with Carb Cleaner.

 

At cold star, unplugging the IACV, the idle is around 1,000-1,500. And unscrewing the screws just so i can see the inside of the IACV while its plugged up and what happens when I start the car. But anywho, unplugged it idles around 1,000-1,500. Plugged - 200ish.