Marc01

Well, my fresh engine install is presenting yet ANOTHER problem. I wired in the knock sensor, I swear the original connection on the harness vanished. Tightened some oil lines down. Made sure airpump was connected correctly (aka 2" rubber hose between hardline from engine to hardline for cat). Car idles much happier, much more steady. I was happy with it.

So I made plans to drive out about 50 miles to a friends house. Was all stoked to go. Got in the car and drove. I noticed that the oil temp was 6 degrees higher than it used to be. 78 c instead of 72c. And 72c is in the summer, right now its barely 30 f outside. I was expecting much cooler temps. But, didn't think THAT much of it. Figured it was something to be watched, and looked into, but not urgent. The car felt sluggish, and even bucked. Almost like it was stalling at 3k.
The boost guage shows good vacumm and good boost. Boost comes on quick and readily. But as soon as the car goes into boost, it feels like somebody throws on the brakes just as much as I'm gassing it. Instead of exploding ahead like it did on the old tired engine, it bogs down. After about 3 tries of this and getting all the way to 10 psi easily. I decided to check to see if maybe I could see any lines knocked loose, or something. I opened the engine bay, and looked down at the turbos, and found they were glowing orange. I know they can do that, but I wasn't pushing the car at all. And its not exactly 'hot' outside. So I'm left saying WTF? The car refuses to idle when its hot and the turbos are glowing. It gets better if I unplug the airpump.

I let the car cool, started it up. Starts no problem, hot cold, whatever doesn't matter. I tapped the throttle in 1st, to see if I still had the boost issue. It took off just fine. 2 minutes down the road, I watched the oil temps raise past the normal 72 to 78, then hit the gas to test it, and sure enough same symptoms. The car is bogging down, badly, under boost. Almost like there is some kind of secret switch that throws on the brakes as soon as I hit boost. Also, the airpump is making a sound like a boost leak. I thought it WAS a boost leak, until I unplugged the airpump and it went away.

Summary:
Bogs down on boost
Turbos glowing orange during easy driving
Won't idle once hot
Idle is helped by unplugging the airpump

WTF? Anybody have any ideas. I was thinking maybe clogged cat? But I looked at the cat, and it wasn't glowing and didn't seem abnormally hot.

Marc01

Nobody has any idea huh?

tiger18

iTrader: (1)

have you got precat downpipe on,,,,sounds like blocked cat? just a maybe

tiger18

iTrader: (1)

ohhh another thing,,, have you tried pulling ECU codes,,,,, sounds little like limp mode,,,,but normally you cant make much boost.

Marc01

No, I have no precat. I do however have the stock cat. My plugs are just about shot. And after cooling down a bit and being more objective, I think it might be ingition breakup. Which would be caused by worn out plugs. I've cleaned the plugs twice with a media blaster. Which normally works about once. Today I'm going to go out and grab some new ones, swap it out and see if it magically disappears.

Marc01

Put the new plugs in. The car is running noticably better. Still boost is hesitant, and it won't idle. I can coax it down to an idle. But it will gradually fall off and die. It will also die while rolling down the street in neutural. I'm going to take it in monday to the dealership to check the timing. And still looking to get a high flow cat.

Anybody have one laying around for cheap?

DaveW

Just a note - a blocked cat (even a really bad one) should have almost no effect at idle, so I'd look for something else first.

Blocked cats show up at higher power levels and whether the car is warm or cold.

Marc01

Yeah, I want one anyway, and it will just take away the possibility. On the other hand, I am going to pull the codes from my ecu here in a few minutes.


I need to check the MAP sensor, I was told it could possibily have something to do with it.

areXseven

iTrader: (1)

Possibly bad fuel,.. or low octane fuel. My FD did the same thing (bogging at boost) when I realized my son had put 5 bucks of regular 89 octane fuel a few days before.

After hanging him by the Cojones,.. and about 2 fill-ups with 93 octane, the car was back to normal.

Marc01

Problem FOUND!

The fuel is good. Good point though.
The cat is fine (although still want a high flow =) )
It was the settings in the PFS purple box. Keep it simple stupid.
As a last ditch effort before continuing digging through the hardware in the engine for a problem. I decided to check the maps on the PFS one last time. When I went into the setup for it, boost was set to "no". So what was happening, was the wastegate was opening at anything above atmospheric. I just changed that one option to a yes, and set boost to 10#'s and she started up and idled fine. I still haven't boosted over .5 bar, but boost came on, and instead of bogging, it started to take off. As much as it can at like 1/8 throttle =). Takes a steady foot to keep it under .5 bar. Oil temps stayed down where they are supposed to. Everything is like it should be. Idles between 800 and 830. Its glorious. Feels great to fix the car, even if it was only broken because of my stupidity =)

Thanks for all ya'll suggestions.
Its always nice when people post how the problem was actually fixed when they do fix it. Helps a lot when using the search function =)