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View Full Version : wtf happened? (...long story, need help)



KAG
09-06-2008, 11:14 PM
(shortened for relevance)

Yesterday morning, I did an oil change at my friends shop 20 min. away. I went with Royal Purple 5w-30 and a mobil 1 filter. The car drove home excellent, and felt the same way it did before the oil change.

When I got home, I wanted to check up on the rest of the engine to make sure everything was intact. The one thing I noticed that didn't look right was that the bottom of the intake box that holds the air filter (K&N) was about 3-4mm away from the bottom of of the box that's connected to the throttle body.

I pulled off the intake and saw that the tabs on the bottom weren't in the slots on the (throttle body) box.

For the week prior to this, I had the snorkus removed. I realized it didn't do much of anything, so I put it back on when I put the intake back on.

I started the car up. This time, instead of the rpms starting at 1500 and coming down to around 750, it dropped immediately to 750.

I backed up a few feet, very slowly. When I let off the gas and put my foot on the brakes, the car bogged down almost to 100 rpms, and I could feel it struggling. It took no more than two seconds to get it back up to a smooth idle again.

Took it for a test run around the block to see if anything would happen. It actually felt like it accelerated better than it did before, believe it or not. Right before I pulled into my driveway, the car stalled on me. The gauges lit up and I felt the power steering go away. I had the clutch in for about 2 seconds before it stalled.

Started it back up...it gave a VERY rough idle. I barely made it into my driveway before it stalled again.

Now, it still starts up and idles fine. I can rev it in place, it still sounds healthy. Once I move it, either in 1st or reverse, it goes down to near 100 rpm again where it feels like it stalls, then it goes back up.

No check engine light or anything.

My car is 100% stock, and has always ran flawlessly. Always starts immediately, always accelerates perfectly, and always idles smooth...until now.

Please give me some input on what I did wrong and what I should do to fix it.

Thanks!

J.McDonald Knives
09-06-2008, 11:38 PM
Check the big intake hose just under the MAF. It may have come loose. It will be hard to see from on top.

2.5GT
09-07-2008, 12:35 PM
right, check all the vacuum hoses and check the connector for the MAF sensor. Other than that, I don't see how a oil change could cause you to stall like that...maybe it's just operator error :wink:

Sarra
09-07-2008, 02:13 PM
Reset your ECU?

KAG
09-07-2008, 02:32 PM
Reset your ECU?
Yep. I disconnected the negative battery cable and stepped on the brake for 30 seconds. No difference.

McDonald and 2.5GT, you mean MAP? My car is a 2000, so no MAF sensor.

J.McDonald Knives
09-07-2008, 02:33 PM
Reset your ECU?
Yep. I disconnected the negative battery cable and stepped on the brake for 30 seconds. No difference.

McDonald and 2.5GT, you mean MAP? My car is a 2000, so no MAF sensor.Still check your vacuum lines.

1-3-2-4
09-07-2008, 04:24 PM
Another vote for the vac lines..

I remember I snapped a plastic piece off when it was around 0F outside.. car was ok until you turned on the defrost which turns on the A/C it was a vac hose and it caused the car to bog and stall if it was not warmed up enough..

summer was a pain in stop and go traffic..

KAG
09-07-2008, 04:46 PM
Just took the car for another run.

I drove it easy at first, then went a little harder. Once I went full throttle and came back down, it stalled. I was going 45 mph w/ no power steering in neutral :shock: Pulled over and started it again.

Reset the ECU again. This time, waited a little longer with the neg. battery cable disconnected.

I drove it super easy this time around, no stalling. Let it idle for a while, then backed up slowly. It still drops down to almost 100rpm when I stop, but it doesn't completely stall. It goes right back up to an easy idle at 750rpm.

Does it take a little bit of driving for the ECU to get used to everything again? I remember reading that somewhere, and I'm thinking if I just drive it around easily for a little longer, it'll fix itself.

Vac lines all look good, I promise.

J.McDonald Knives
09-07-2008, 05:03 PM
they may look good but when they heat up they expand and the leaks can come from that. You may have to smoke them to see if there are leaks. Other than that it might be your clutch not disengaging all the way causing it to still be in gear and causing it to stall.

decke48
09-07-2008, 05:30 PM
yeah i take the ecu to relearn everything in about 500 miles unless you follow a drive cycle check

KAG
09-07-2008, 07:57 PM
I'm stumped. I have no idea what it is, and I need this car running by tomorrow.

I checked out the plugs, they're good.

Is there any chance it could be the clutch? I've realized that it only bogs down and stalls if it's in gear with the clutch in. If it's just in neutral, it wont stall. The clutch has never slipped though, and it still feels good.

If it's not the clutch, then... :cussing:

J.McDonald Knives
09-07-2008, 10:20 PM
Try stopping with it in neutral and see if it fixes the problem. I always put it in neutral when I start to stop.

KAG
09-07-2008, 11:22 PM
Try stopping with it in neutral and see if it fixes the problem. I always put it in neutral when I start to stop.
Well...it doesn't fix the problem, but it does prevent it from happening.

I'm replacing the clutch fluid next to see if that does anything. Hopefully that'll help...

J.McDonald Knives
09-07-2008, 11:33 PM
Then there is your problem. Check everything. Make sure to have a buddy there while you are bleeding the clutch. Its just like bleeding the brakes but it DOES require 2 people to do it, IIRC.

Legacy89
09-08-2008, 02:33 AM
Just took the car for another run.

I drove it easy at first, then went a little harder. Once I went full throttle and came back down, it stalled. I was going 45 mph w/ no power steering in neutral :shock: Pulled over and started it again.

Reset the ECU again. This time, waited a little longer with the neg. battery cable disconnected.

I drove it super easy this time around, no stalling. Let it idle for a while, then backed up slowly. It still drops down to almost 100rpm when I stop, but it doesn't completely stall. It goes right back up to an easy idle at 750rpm.

Does it take a little bit of driving for the ECU to get used to everything again? I remember reading that somewhere, and I'm thinking if I just drive it around easily for a little longer, it'll fix itself.

Vac lines all look good, I promise.

I found a similar problem in a Volvo 940 last weekend. Driving trough the forest doing about 60/70mph, when i come up to a hairpin i clutch, brake and change gear.
2 seconds after i hit the clutch the engine stalls. I hit the brakes hard since the servo is gone, firing up the engine again doing 40mph, shifts gear in a hurry to make the turn.

That was the scariest turn Ever!

No idea what the problem is tough, just gently engage the clutch seems to work. The engine stays on and i can change gear and brake.

KAG
09-08-2008, 05:04 PM
Drove the car a lot more today. No problems, no stalling, no bogging down. Everything's good. :cool:

I did replace the clutch fluid last night like I said I was going to do, but I really doubt that an extremely minor thing like that could make a car bog down like it did...

My guess is, it just took the ECU a little while to relearn everything and adjust. That to me just sounds like the most logical explanation.

Looks like I might be getting a new clutch now after all, since this OEM one sucks, and I'd be lucky to even get another 10k more miles on it anyways. I'm thinking just spend the extra money and get one from ACT... There goes my suspension fund!

Ah, well, thanks for all the help.

Legacy89, yeah, it definitely felt weird turning the car on going 45mph...

Legacy89
09-08-2008, 07:21 PM
I'll tip my friend about that tomorow, maybe he just needs an ECU reset. Its a 940 TIC but i dont think this case is any different.

J.McDonald Knives
09-10-2008, 12:44 AM
You might have also just had an air bubble in your clutch hydraulic system.