I am running a stock turbo and intercooler with a stock long block. only real mods are 36# injectors, JC 110 race chip, 340 walbro,my best run was a 12.978@105.42 running about 22-24 pounds of boost. My question is on the 2-3 shift the car would loose boost and would go down to like 12 pounds and then slowly rise back up to 23. what could be causing this? 02's were good about 800 with no knock.
Just got back from the track
- Thread starter stss96
- Start date
I am chasing the same problem! It is a PITA. I am going to install a ground relocation kit. Then check the positive battery cable under the passenger head to make sure it is not grounding out on the shift. Belt slipping?
I just can't seem to get any free time to diagnosis it lately, I will let you know if I figure it out, let me know if you find the problem first?
I have been getting some weird readings from Turbolink, but I'm not sure if I am logging good data yet. I don't think it is the laptop's fault as some have been experiencing.
I just can't seem to get any free time to diagnosis it lately, I will let you know if I figure it out, let me know if you find the problem first?
I have been getting some weird readings from Turbolink, but I'm not sure if I am logging good data yet. I don't think it is the laptop's fault as some have been experiencing.
I'll offer up a couple of possibilities:
1) Short shifting into 3rd gear - should shift about 60+ MPH
2) Running too rich. O2s should be high 700 range.
3) Back pressure from catylitic converter or restrictive exhaust.
4) Leaking driver side exhaust manifold
5) something in the chip program
6) Bad wastegate solenoid or actuator
Good luck in finding the problem.
1) Short shifting into 3rd gear - should shift about 60+ MPH
2) Running too rich. O2s should be high 700 range.
3) Back pressure from catylitic converter or restrictive exhaust.
4) Leaking driver side exhaust manifold
5) something in the chip program
6) Bad wastegate solenoid or actuator
Good luck in finding the problem.
blackbuick87
Senior Member
- Joined
- Mar 11, 2002
Was the convertor locked manually or is it programmed into the chip?
2.) I know my O2's were fine when I had the same problem, at least that is what the sensor reports (If you can trust it).
4.) I know I don't have a header leak. swapped it out already.
5.) Chip program should be great, Thrasher 92.
3.) My exhaust could use a little opening up, I have two chamber flows with a high flow cat, but I don't think that is the problem.
6.b.) I think the wastegate solenoid is fairly new. I guess I could hook it up to a DC power supply and check it's performance? Can someone tell me the part number for the grainger bleeder valve? Or do I just go to the local grainger and ask for a small bleeder valve? Perhaps hooking the car up tuning style will help?
6.a.) I think the actuator might be a good bet since 3rd gear puts the most load on the system. I have actually seen my actuator bounce and flutter the need when boost is increased over 22psi in 3rd.
The reason I am looking for a short is because I have seen my TPS voltage drop at times and I see voltage drops and huge detonation readings upon shifts. Sounds like a short, I am pretty sure it is not Turbo link reporting erronious data.
any of this sounds familar to a short or ground of the pos. batt cable.
4.) I know I don't have a header leak. swapped it out already.
5.) Chip program should be great, Thrasher 92.
3.) My exhaust could use a little opening up, I have two chamber flows with a high flow cat, but I don't think that is the problem.
6.b.) I think the wastegate solenoid is fairly new. I guess I could hook it up to a DC power supply and check it's performance? Can someone tell me the part number for the grainger bleeder valve? Or do I just go to the local grainger and ask for a small bleeder valve? Perhaps hooking the car up tuning style will help?
6.a.) I think the actuator might be a good bet since 3rd gear puts the most load on the system. I have actually seen my actuator bounce and flutter the need when boost is increased over 22psi in 3rd.
The reason I am looking for a short is because I have seen my TPS voltage drop at times and I see voltage drops and huge detonation readings upon shifts. Sounds like a short, I am pretty sure it is not Turbo link reporting erronious data.
any of this sounds familar to a short or ground of the pos. batt cable.
Well I ran a little rich at 800 because on the first run i had my fp a little bit lower and the car leaned out to 715mv so i had to let off and get back on it and still ran a 13.0. I just put on a new drivers side header its not leaking. The converter wasn't locked manually however i don't know if the chip was locking it. My acuator is new. I am running a test pipe and a hooker cat back not much restriction there. I am not sure about when it shifted into 3rd no tach yet.
BADINBLACK6
Member
- Joined
- Jul 30, 2002
gn231 don't you have to gut your cat or use test pipe with a thrasher chip? I don't know if that could have any effect.
BadinBlack, Yes I am running a highflow cat with the thrasher chip. Probably not a good idea since I think the over rich idle preset in the thrashers is very hard on the cat. I am going to go to the hooker setup with the test pipe in the next few months and just use the cat for emissions testing.
GNSS,
Thanks for the tip, sounds like that could be very possible for my problem. I know my idle and WOT values look good, but then again, it is the original MAF in the car. I tried giving it a tap at idle with a screwdriver and the car didn't stutter or anything. I will not rule out the bad MAF, maybe it is a good excuse for me to go with an lt1 and translator
The strange thing is, the car runs like a champ in 1st & 2nd, then boost drops after 3rd shift and slowly builds back up!
GNSS,
Thanks for the tip, sounds like that could be very possible for my problem. I know my idle and WOT values look good, but then again, it is the original MAF in the car. I tried giving it a tap at idle with a screwdriver and the car didn't stutter or anything. I will not rule out the bad MAF, maybe it is a good excuse for me to go with an lt1 and translator
The strange thing is, the car runs like a champ in 1st & 2nd, then boost drops after 3rd shift and slowly builds back up!
