I am stumped... I just noticed the other day that I wasn't hitting my peak boost levels at WOT...19psi. I am hitting around 15 psi. Additionally, I have had a lot of popping between shifts and on decceleration, so the car is running richer than normal. So for the past couple of days I have been checking all of my lines, but I can't seem to find where the leak is coming from...if it is in fact a leak. Then today I drove out to Peachtree Industrial to do an errand, I was on the highway for about 20min. I get off and go do my errand, and when I am about to get back on to the high way I notice that my car is acting really strange. The more gas I give her the more power and boost I am losing. As the engine rpms were climbing, the boost pressure was droping. (maybe the ECU was pulling timing) Then she stalled. I got out of the car, did a once over on the engine bay, everything seemed like it was in place, and no CELs yet. So, I cranked back up and tried to at least get my car off of the road and out of traffic. For a few hundred yards the car drove okay and then it started happening again. So I quickly pulled off into a lot, and shut the car off. For the next 10-15 minuites I would periodically check the idle. It was getting more and more rough with every try, the idle began to surge. It would almost stall, and then surge back on. Finally the computer throws a CEL So, I pulled out my Access Port and pulled the codes P0102, and P0113...which were both MAF sensor codes. Unfortunately, I had no screwdriver, or any brake cleaner with me, so the best I could do was unplug the MAF and plug it back in...which surprisingly enough fixed the rough idle. I let it sit at idle for a good 10 minuites before makeing the decision to drive the 20 miles home. I kept my speed steady and made it home without any incident. When I got here I pulled the MAF sensor out and checked it for dirt, it was a little scummy, but nothing serious. Just to be safe, I cleaned it off and reinstalled. The idle is fine, but the boost issue is still there. Now, the turbo can't build anymore than 5psi... There is a slight rattle coming from the area of the turbo, I can't tell if it is the turbo making the noise or some parts rattleing against each other with the engine vibrations... Is my turbo dying or could I possibly have a large hole somewhere I can't see...(the bottom of the turbo inlet hose for instance) C/N: Turbo can't build more than 5psi CELs P102, and P0113 (MAF codes) Checked MAF sensor No visible line leaks All hose clamps tight
I can't tell you for sure your're problem but I can offer this experience... I was on the way to work a couple of months ago when the turbo outlet hose to the I/C blew off under boost. The turbo "woosh" noise was alot louder but I surprisingly was still hitting 17psi as read from the intake manifold. My boost gauge is VERY accurate as compared to enginuity data logging. I stopped to check the problem and drove the additional 25 miles to work w/ no problems except reduced power and a lot of noise. Another issue I've seen quite often is the turbo inlet hose splitting on the bottom just before the turbo due to oil intrusion from not using catch tanks. Hope the info helps!
Okay here is the lastest news. I don't know why I didn't think of this before, but to help me narrow down the possiblities, I pulled the vacum line to the wastegate and went for a spin around the block...sure enough boost went well off the guage, just as it should without the wastegate there to control it. (I quickly pulled over and reinstalled the vacum line) So, this means that I infact DO NOT have a boost leak, and my problem is coming from either my BCS or the Wastegate itself. This is some advice that I got on Nasioc... That is exactly what is going on. If it is infact a problem with the wastegate...is the wastegate serperate from the turbo, or do I need to replace the whole turbo? Also, if my wastegate arm has been tightend and my tune was done on the tightend arm, then if I get a new wastegate, it too needs to be tightend the same amount in order to jive with my tune? Sounds like a headache... On a side note, cleaning my MAF resolved the rough idle issue 100%
He's probably talking about the wastegate ACTUATOR, not the wastegate itself (which would be an unlikely candidate).
yes, he is talking about the wastegate actuator...and I should have made it clear that i wasn't talking about the actual wastegate inside of the turbo. just to be sure though, the wastegate actuator is the little cylindrical assembly that sits just to the left of the compressor on the outside of the turbo? How can I "test" it, or check it for normal operation?
Okay, I have a new question. I just had an RA gearset installed in my car, would the new gearing affect the Wastegate Duty Cycles?