97 GSX Bucking at WOT like hitting a wall

[trung_n_nguyen]

Hi guys, I've been searching through all the post and comments for this problem and I'm giving up trying figure thing out by myself. I'm DESPERATELY need help. I'm just purchase a 1997 Eclipse GSX, the car is completely stock except for the intake, exhaust, 1G BOV (uncrushed), boost gauge and a manual boost controller. The car drive around fine if I keep it under 32000rpm. Here's my problem: at every gear when it hit 3500-4000rpm or when I WOT it feel like I slammed on the brake. Like I hit a wall. The boost gauge show 5-6 psi (not dropping until I let off the gas or go to the next gear). If I keep my foot on the gas pedal and try to accelerate the car feel like riding a horse (it bucking) and will not go pass 4500rpm or accelerate any further or produce anymore powre. The check engine like was on with code P1104 (wastegate solenoid malfuntion). The boost control solenoid was plugged in. My manual boost controller was turned all the way down. I did the boost leak test and it was fine. I've replaced the spark plug with NGK BPR6ES (gap them at .28) and NGK wires but problem still exist. Please help I'm begging you.

 

[96awd]

Wastegate isn't producing boost. I'd replace the solenoid.

 

[trung_n_nguyen]

Wastegate isn't producing boost. I'd replace the solenoid.

I have the manual boost controller hook up to by pass the OEM boost control solenoid.

 

[kenuwine4g63]

remove the bcs and run a line from the intake manifold to the actuator on the turbo. It will run at spring pressure which should be 10-15psi on a t25. It also sounds like a boost leak and a big one. Do another BLT, and try again check your lower injector seals, biss screw o-ring, all vacum hoses, intercooler and intake gaskets. Im pretty sure thats what it is. If not you have link and its stuck on anti-lag when your driving and you dont know it. (I've had that problem before) amazing huh?

 

[trung_n_nguyen]

Wastegate isn't producing boost. I'd replace the solenoid.

I checked the solenoid itself and got 38 ohms. and there's power going to it. I just don't know if it still working. How do I know for sure that the solenoid working or not. Thanks.

remove the bcs and run a line from the intake manifold to the actuator on the turbo. It will run at spring pressure which should be 10-15psi on a t25. It also sounds like a boost leak and a big one. Do another BLT, and try again check your lower injector seals, biss screw o-ring, all vacum hoses, intercooler and intake gaskets. Im pretty sure thats what it is. If not you have link and its stuck on anti-lag when your driving and you dont know it. (I've had that problem before) amazing huh?

On my intake manifold there's one vacuum line hook up to the BOV so you want me to take that line and connect it to the turbo's actuator? and what do you mean by I have link? Thanks

 

[MrBoxx]

Bypass your MBC completely.

Take the pressure signal line from your intercooler pipe or turbo compressor housing (the one going IN your MBC) and connect it directly to your wastegate actuator. This should give you 10-11psi of boost.

When you did your boost leak test, how high did you pressurize the intake tract? How long did it hold pressure? Were you looking at your aftermarket boost gauge for this information or the compressor gauge? Did you spray soapy water on the engine compartment, intercooler, intercooler pipes, blow off valve, intake manifold, throttle body, injector seals, etc at the time?

 

[crusada]

if the ecu is socketed for DSM link its a tunning program i doubt its on there if the car is pretty well bone stock and yes thats what he was saying i believe

 

[2GFWDbeast]

sounds like fuel cut. I had same problem with my 97 gst. Felt like i hit brick wall.

 

[Colt4G63 also]

If your factory boost gauge reads really high, and your aftermarket one reads really low, then you sir have a boost leak.

 

[GsXdSmKingGsX]

1)Spark Plugs
2)Spark Plug wires
3)Bad fuel line
4)Boost leak

 

[kenuwine4g63]

Bypass your MBC completely.

Take the pressure signal line from your intercooler pipe or turbo compressor housing (the one going IN your MBC) and connect it directly to your wastegate actuator. This should give you 10-11psi of boost.

When you did your boost leak test, how high did you pressurize the intake tract? How long did it hold pressure? Were you looking at your aftermarket boost gauge for this information or the compressor gauge? Did you spray soapy water on the engine compartment, intercooler, intercooler pipes, blow off valve, intake manifold, throttle body, injector seals, etc at the time?

Do this^^^

It shouldnt be fuel cut because its only 6-7psi of boost, it sounds more like a boost leak. And yes i had link on one of my gst's and it was stock it had a e316g and when it started to pull it bucked because of the anti-lag that was on it and it wouldnt go past it. had to swap ecus. I keep forgeting that most people have nipples on the compressor housing of the turbos. Do exactly what mr.boxx said

 

[trung_n_nguyen]

Bypass your MBC completely.

Take the pressure signal line from your intercooler pipe or turbo compressor housing (the one going IN your MBC) and connect it directly to your wastegate actuator. This should give you 10-11psi of boost.

When you did your boost leak test, how high did you pressurize the intake tract? How long did it hold pressure? Were you looking at your aftermarket boost gauge for this information or the compressor gauge? Did you spray soapy water on the engine compartment, intercooler, intercooler pipes, blow off valve, intake manifold, throttle body, injector seals, etc at the time?

OK, I did what you said: I took the vacuum line from the compressor housing and connect it to the turbo wastegate (problem still exist). I will do the BLT tmr because it's raining outside and I don't have a garage. Will keep you update.

 

[architechnik]

Plug in your MAF. Your wiring is loose. Or you have a massive leak after the MAF and before the turbo.

 

[necrotopsy]

this really sounds like an ignition problem to me.

not sure if the 4g63 uses a coilpack or a distributor, but you might want to check that out since you already replaced the plugs/wires.

 

[trung_n_nguyen]

this really sounds like an ignition problem to me.

not sure if the 4g63 uses a coilpack or a distributor, but you might want to check that out since you already replaced the plugs/wires.

It use the coil pack.

I don't know if this will help but when I try to start the car it took almost 5 second for the car to start and it sound very weak.

 

[razrman8]

I agree with what Eric said. It is easier to check the simple stuff first. Completely eliminate the boost controller. Run a vaccum line from the boost source, since you are running 16g j-pipp nipple of sorts, to the wastegate actuator. It will assure that your manual boost controller is not messing up. Also, did it just start doing this?

 

[trung_n_nguyen]

I agree with what Eric said. It is easier to check the simple stuff first. Completely eliminate the boost controller. Run a vaccum line from the boost source, since you are running 16g j-pipp nipple of sorts, to the wastegate actuator. It will assure that your manual boost controller is not messing up. Also, did it just start doing this?

I'm running on a t25 turbo so there's no J-Pipe of any short. The car still using the side mount intercooler. I did connected the vacuum line from the compressor housing to the turbo wastegate actuator. And yes it's just start doing this 2 weeks ago.

 

[razrman8]

Bypass your MBC completely.

Take the pressure signal line from your intercooler pipe or turbo compressor housing (the one going IN your MBC) and connect it directly to your wastegate actuator. This should give you 10-11psi of boost.

When you did your boost leak test, how high did you pressurize the intake tract? How long did it hold pressure? Were you looking at your aftermarket boost gauge for this information or the compressor gauge? Did you spray soapy water on the engine compartment, intercooler, intercooler pipes, blow off valve, intake manifold, throttle body, injector seals, etc at the time?

Alright. You need to update your mod list on your profile then. Or things like that could happen, improper diagnosis. No biggy, just get it fixed. Did you do the highlighted above yet? If not, it would be a good thing to do.

YouTube - Boost Leak Testing 201: Using the tool.

 

[trung_n_nguyen]

Ok, did you do this? If not, it would be a good thing to do.

YouTube - Boost Leak Testing 201: Using the tool.

I did that after I bought the car 2 weeks ago and things was fine then. I haven't had a chance to do it today because it's raining outside. I'll do it tmr and keep you guy update.

 

[YanDsm]

It isn't boost leak. I had same problem on my 93 talon. It's the knock sensor wires or sensor itself. The ecu see very high knocks, retard timing and thats a brick wall. Trust me

 

[razrman8]

I didn't say that it was indeed a boost leak. It is just a common thing to have a boost leak and think it is something majorly wrong. Thus, anytime something like this occurs, a boost leak test is mandatory. Only checking to make sure.