I dont understand. The car revs fine while parked but as soon as its on the road for 3 minutes and I go half on the throttle. it hesitates and sputters and seems to lean out at about 2600 RPMs.

From my previous session I did all grounds and then some
stock injectors
calibrated TPS even ran it w/o TPS to switch it to full rich
255 Walbro
T2 pressure sensor + ECU
wastegate not even hooked up (breaking it in as NA)
new fuel filter last night

-Car has perfect oil PSI and doesent get hot at all. Porting is very agressive but that shouldnt affect anything.


WTF!!!!! is wrong with my car???

 

Adjust the tps again turning clockwise and I bet you the problem will go higher in the RPM range. Keep going so that you no longer have the problem anywhere but with closed throttle you still read o% (recommend finding a SAFC to help with this, or check factory ohm values). The TPS's in these cars are garbage except for FD.......... so you should just convert to FD upper manifold and everything will be fine!

 

Yeah TPS is very picky. Even changes in the weather can affect it. Also Why are you running a T2 ECU with an NA engine? That's what it looks like you said anyway...

Check your spark plugs and timing.

 

no no no. Its a Turbo 2. I just havent hooked up the wastegate so that it never boosts up while I break it in. The motor has about 3 miles on the rebuild. I have a SAFC but no wideband to tune it off of which is why I havent installed it. Timing is ok. So should I just not use the TPS? I'll try adusting it and hopefully the problem stops.

Thx guys

 

did you disconnect your injector harness plugs while doing any of the work? The reason why i am asking is that you could have disconnected the water thermo switch located behind the upper water neck on the water pump housing. Which may cause your inability to go drive anywhere.

 

I did actually disconnect them. I'll check on that Thx

 

Wouldn't having the wastegate not open cause huge boost spikes? Shouldn't the wastegate be stuck in the open position to avoid boost. I am not a turbo expert, but I am pretty sure when I did my turbo swap, the wastegate allowed extra exhaust to bypass the turbo, and go straight out. Not hooking that up and running with it closed all the time, will probably create massive boost, really quick.

But, I am not an expert.

 

Right. the wastegate is not allowing boost to build. I'm taking it easy for a few hundred miles then going boostin around town but not with this stupid problem.

 

what he is trying to ask is are you wiring your wg open/disconnected from the actuator arm or did you just remove the vac line? when you say wg is disconnected it sounds like you mean you did not attach the vac line

 

yup, and with the vac line disconnected, it could cause some problems.

 

Its on there just allowing a bypass. Its fine. But thats not my concern. I'm trying to figure out why my car is acting up. I get to wrench on it tonight so I'll try all of the above then keep you guys posted

 

Bypass? Hmm, i don't know if your car has it, but if the wastegate is staying closed, and you are spiking boost, then I know in some cars, they have fuel cut for higher boost levels. You have a FCD?

Just thought about it when i was driving to the university today. Too much boost without a FCD would cause problems. And, would only occur under load. But, if you say you know that the wastegate is tied open, then I would say check all sensors.

So, you see, I am saying if the wastegate isn't hooked up correctly, then it could kill your power.

Check:
Fuel injectors,
boost sensor,
afm,
fuel pressure,
etc.

Link to how the wastegate works.
http://www2.turbov6camaro.com:443/gate.htm

 

What he is doing is a common break in trick. Leave the arm off and the wastegate just flaps around, any pressure of any kind will open it up. I did this same thing with a friends CA18DET after a full rebuild. Now for the TPS: you have to jump the check connector each time you make an adjustment but you should have the car running while it is jumped. Jump the wire with ignition on, turn the screw, ignition off and take out jumper, then load test the car (drive it). If it is not good yet, keep repeating until you get it right.


Checking the voltage (ohm) on TPS sensors doesn't really work reliably anymore with how old our cars are. Corrosion and crap inside and in the wiring of the TPS will cause different resistance to be seen from your voltage meter (tester), so you need to adjust it and try your adjustments manually to get the desired affect. I just dealt with this on a turboII last week. The senor ohm'd out great at the setting it was at, but still was being a little bitch, so I did the above mentioned method and got it right.

 

Exactly. The wastegate is flappin in the breeze per say LOL so I'm not building boost. I do have a RB FCD so I'm good. I will try your suggestions today. I do have a feeling the TPS is acting up.

Question: Will running the car with TPS unplugged effect it? Can I just do that?

Also: Can I use the S5 NA TPS by putting it on the T2 bracket? Will it read correcty???


THX guys

 

s5 NA and turbo TPS are the same just swap the bracket. the wire color may be different but they should all go to the same pins.

when you tested the resistance on the TPS did you do a slow gradual sweep through the whole range? your TPS might be set fine but there may be drops or spikes in resistance. Do a full slow sweep and watch the numbers and see if they climb gradually without dipping or spiking.

 

Havent tested the resistance yet but I try everything to calibrate TPS

 

test the actual resistance, prolly is either open (infitiy reading on ohm meter) or shorted (less then 4ohm at WOT).

 

in my notes*

 

It sounds like you have a boost leak with no boost!

Since the intake tract is still going through the IC and Id bet youre still making at least even pressure in there (if not slightly positive) I would build a $15 boost leak tester and look for leaks. Take the disconnected WG out of the picture and you have classic boost leak symptoms.

 

Ok so Friday I tried EVERYTHING I could think of. We calibrated the TPS, switched out coil packs, checked grounds, tried a different ECU, checked spark, changed battery...

NOTHING. The car will rev fine for a bit while sitting there but as soon as I drive it on half throttle it chokes and bogs out. The car is running super rich BTW. If I tap the pedal full throttle, it'll instantly choke and caugh a huge fireball.

NOTE* something is killing my batteries. It was full charge on friday then last night it was completely dead. Also while idling, the lights on the car fluctuate. they'll be full bright then dim out then go back to full bright. I havent gotten a chance to check current as I dont have a volt meter but will do so today. just wanted to let you guys know the symptoms and status.

 

boost leak tester.

best $15 you'll ever spend.

 

You're saying I have a boost leak and this is what's causing these issues???

 

timing?

 

I retarded the timing then set it back them advanced it and...well I did everything possible to it LOL!

 

you did check the water thermo connection like i said before right?