I think I cleaned the throttle body but I'm not sure?

drumsagogo · Post by **drumsagogo** » 10 Oct 2007, 19:48

I had a bad stalling problem within the past couple days with my 1996 850 turbo. I did a lot of reading....make that A LOT of reading since I digested the entire sticky stall thread AND cut and pasted various posts to make some notes.

Based on the thread I concluded the 1st thing I should do would be clean the Thottle body (the quick easy way without removing it).

I had 3 sets of instructions in front of me and a diagram culled from the threads here. I removed the black plastic cover that was mentioned and then, I had no idea what to do.

I could barely tell what the throttle body was?
There were a bunch of hoses coming in and out of this thing and a cable and none of the directions I had clearly stated any order or disassembly or procedure to follow for the cleaning.

A mechanic happened by (I work at a diesel shop) and told me to take of this big 2" or so hose on the left lower side and to clean in there.

After I removed the large lower hose, I could barely get a finger in to the input area of (what I think) the TB. After some more advice, I removed the entire section of piping that runs up towards the radiator. After doing this, I could push the big rubber piece down enough to see the "butterfly valve" flap thingy that was refered to in my notes (i think)...there was some carbon build up but nothing I though looked exceedingly bad.

Anyway, I gently pushed on the flap with a screw driver and it didn't move, so I sprayed the outsided of flap with carb cleaner and generally brushed that area off. I then reassembled the piping.

Of course 3hrs later my car stalled again.

What I did wasn't hard, but I have no idea if I did what people are talking about here when they talk about cleaning the Throttle body? Do any other hoses have to be removed? If so which ones? Is this build up only in this 2 or 2.5" hose?

I generally do pretty good at this stuff, including having replaced my heater motor, repaired horn contacts, and r&r the ABS module...thanks in large part to the advice offered on this site...but I admit...I am totally lost on this one! I guess I need total beginner advice? Thanks for any input.

Post by **MadeInJapan** » 10 Oct 2007, 19:58

You did pretty good...you cleaned the outside of the throttle body. If you really want to clean it, you'll have to take the piece with the butterfly part completely lose from the inake...that typically means you'll need a new throttle body gasket. If the outside isn't bad, I doubt that the inside is that bad either and so my opinion is that you should look elsewhere for your issues....maybe some small vacuum hoses that are cracked and allowing unmetered air into the intake.

tripleb · Post by **tripleb** » 10 Oct 2007, 20:14

I'll have to agree with MIJ, the throttle issues you may have read about really started with the 1999 models.

Have you checked for trouble codes (dtc's) yet? I hear some places may do it for free. The dtc's really can help in this type of diagnosing of a driveability complaint.

Check all the vacuum hoses and intake piping for leaks. Make sure all the clamps are tight for the piping.

Kinda sounds like the MAF sensor or a fuel pump, but try to give more info (dtc's, and conditions when stalling. Does it restart immediately?)

Post by **MadeInJapan** » 10 Oct 2007, 20:24

Right....even if the TB is dirty, as long as the butterfly closure completely closes and doesn't stick then it's probably something else on a pre-'99 model. With the introduction of the ETM (electronic throttle body) everything changed.

drumsagogo · Post by **drumsagogo** » 10 Oct 2007, 20:30

Thanks for the input.

The check engine light has not come on. Could there be active codes but no light on? 3-4 months ago I had a weird code, I think it was a MAP sensor code...high side pressure or something? Anyway, I cleared it and haven't had any problems since.

I also bought some MAF sensor cleaner but need to get that T20 security bit to take the housing apart...I will hopefully try this tomorrow.

Then I planned to check the fuel pump relay under the fuse panel.

The stalling only happens intermittently from an idle, though the engine actually did cut out 2x today trying to pull out from a parking spot...i.e. it wouldn't even idle for 15 seconds.

tripleb · Post by **tripleb** » 10 Oct 2007, 20:45

The light doesn't need to be on for a code to be stored.

B

drumsagogo · Post by **drumsagogo** » 10 Oct 2007, 20:46

gotcha and thanks.
I'll check the codes tomorrow as well...

drumsagogo · Post by **drumsagogo** » 11 Oct 2007, 10:40

Ok.
I checked the codes, no codes.

I cleaned the MAF sensor. After unhooking the plug and removing the air filter box cover, I noticed the vacuum line that goes to the bottom of the sensor tube was unhooked, not sure if I did it or not?

Anyway, cleaned the sensor.
Put it back together, plugged in that lower vacuum line again.

Went a test drive to the thrift store-ok.
Went to the grocery store-ok.
Left the grocery store and got about 10ft before it stuttered and stalled.
It continued stalling, well actually the car was cutting out and all dash lights coming on for the remaining 1/4 mile back here to work...about 15 times.

I guess I'll check that fuel relay next...? Hope I can find it...this one is making me nervous...I barely made it back here to work.

drumsagogo · Post by **drumsagogo** » 11 Oct 2007, 12:16

I just took a look at the fuel pump relay...it looks basically brand new.
I am not comfortable enough with my soldering skills to try the recap.
Also, I don't understand how a cap could intermittently fail? Wouldn't it just stop working?

I feel beat on this one.

The only other thing I'd mention is that I think there is something screwy with my thermostat, because last winter, when it was really cold, say less than 20deg, the car just wouldn't warm up...the temp gauge would only be at, say 15% instead of 50% and I'd only have lukewarm heat. Then I'd make a stop, get in, restart, and boom instant heat and the temp gauge would shoot right back up the normal 3:00 position.

I planned to replace the thermostat figuring it was sticking and just remembered now that the weather's turning.

It's a long shot, but anyone think there could be a correlation to the stall?
If there is not sure why it didn't happen last year???

Next step is probably the dealer because I'm at my wits end?!

Post by **matthew1** » 11 Oct 2007, 15:53

T-stat (notes, procedure) or Temp sensor.