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What is this part, and what does it do?


Sideways240sx
03-18-2007, 12:57 PM
So i have yet to get my scanner, to see what code is being thrown, but my dad thinks that his piece may be bad, It looks like it gets vacuum off the tb, and has a possible fuel line going to it? im not sure what it is, again i come fromt he honda world, but there is a 2 pic harness that gets plugged into it. it chatters kinda bad, sometimes, i have no idea if this is why the car doesn't run great when it heats up. thanks.

Hear is a pic of what i am talking about, i circled the piece in red. thanks

http://www.sidewayz.net/olds/olds.jpg

BNaylor
03-18-2007, 01:05 PM
That is the evaporative emissions system purge solenoid. The output vacuum line goes back to the rear of vehicle to the charcoal cannister by the fuel tank.

When bad it should set a DTC of P044X? related to the evaporative emissions system.

Sideways240sx
03-18-2007, 01:37 PM
Could it make the car idle really bad, and die all the time? Thanks for the quick input. chris

BNaylor
03-18-2007, 01:46 PM
I've never known a purge solenoid to cause a bad idle unless there is a problem with the vaccum lines to it. Poor vacuum can cause a bad idle so check all vacuum line connections at the throttle body and intake manifold. The sensor that controls the idle is the idle air controller (IAC). You can try removing it and clean the spring loaded pintle with carb or throttle body spray cleaner. Also, clean the IAC seat throttle body side. The IAC is located on the left hand side of the throttle body. The top round shaped black module with the electrical connector.

Are you geting any SES/CEL light? Also, fuel problems like low fuel pressure or bad fuel injectors can cause a poor idle.

Another component is the MAF sensor.

Sideways240sx
03-18-2007, 02:35 PM
Yes the Engine light is on. I should have a scanner coming on monday or tuesday to scan it and see whats wrong, or what code its throwing atleast. All Vaccum lines appear to be ok. All that i could find at least. The way the car was running i first that it would be the iac, but was unsure which one it was. On my acura its only a 4 banger, but its on the back of the intake manifold. I will try pulling the iac and cleaning it with carb cleaner. Is the iac what i have circle in red below? http://www.sidewayz.net/olds/olds2.jpg


I took this piece off, i believe it is the idle air control valve, but i dont see a way to open it to clean it decent. Thanks, Chris

BNaylor
03-18-2007, 03:11 PM
I took this piece off, i believe it is the idle air control valve, but i dont see a way to open it to clean it decent. Thanks, Chris

That is the EGR valve. Sometimes it can cause a bad idle too so it would not hurt to clean it. Once removed the pintle can be cleaned with carb cleaner. Make sure it moves freely. Then the exhaust tubing part where it mounts on especially at the lower intake manifold.

The IAC is located on the throttle body where the accelerator is connected and the intake ducting from the air filter. Go down about 2 inches in your pic and then to the right. I circled the part in yellow.

http://i5.photobucket.com/albums/y186/lizzywiz/olds2.jpg

The sensor below that is the TPS and to the right, top MAF sensor.

Sideways240sx
03-18-2007, 03:43 PM
I ended up pulling both pieces. The iac was dirty. I cleaned inside where it seats to. The Egr was kinda dirty, so i cleaned that. Put them back in the car still idles rough, and dies. Its the service Engine soon light thats on. I think im done doing stuff till i get the scanner. Im semi tempted to pull the whole tb/maf off the car to clean it out as best i could and see if that helps. I remember on my Acura the car had to re learn the iac after i put a new one in, but i can barely keep the car running so i dont think i have it yet. I will definatly post codes up as soon as i get it scanned, and thanks for all the help today. Thanks, Chris

BNaylor
03-18-2007, 03:55 PM
I agree get it scanned as soon as possible and post the DTC code(s). I would clean the complete throttle body. Lots of carbon builds up in there especially at the butterfly valve (throttle plate). Keep us posted and good luck.

Sideways240sx
03-19-2007, 02:57 PM
Ok, so i got my scanner today. IT started off having 2 codes. P0101 Which it says is Mass of Volume Air Flow Circuit, and P0300 which it says is Random Multiple Cylinder Misfire Detected. I cleared the 2 codes, i let the car run for about 10 minutes, until it warmed up and died, and the only code i got was P0302 Which it says is Cylinder 2 misfire detected. Im gonna try to pull the plugs, and make sure they all look ok, the back ones dont look fun, but any other ideas or suggestions? Is it still possible the car has bad gas? The guy we bought it from says thats what he thought went wrong with it? On a day when i have more time i may try to pull off the entire tb and clean it all out good. Thanks in advance, Chris

BNaylor
03-19-2007, 03:18 PM
Although you seem to be getting a consistent misfire DTC, I would consider looking into the MAF sensor DTC even though it has not returned at this point in time. Misfires very seldom cause to car to die or stall.

Here is a simple test. Disconnect the electrical cable to the MAF sensor and then see how it goes. It may trigger another MAF DTC but that is OK for now. When a MAF goes bad it will cause stalling and a very poor idle sometimes accompanied by black smoke out the exhaust (rich fuel trim). The cold wire element sensor on a MAF will get dirty and sometimes a good cleaning helps. Use MAF spray or electrical contact cleaner only not carb spray. MAF is located on the top of the throttle body right next to that IAC.

Scrapper
03-19-2007, 03:56 PM
MAF massive air flow sensor it's all tied in to computer to tell it what too do....good luck...
i'm out of here for now.....

scrapper.....

Sideways240sx
03-19-2007, 08:01 PM
Where is the Cps, and how hard is it to install? If it was the cps, would it throw a code? For an update, i tried to clean the maf as good as i can, but i cant remove it, because of the circle in the center of the torx bit. I also cleaned the iat i think it is in the intake tube. Both were cleaned with electrical cleaner. Today i put new plugs, and wires in since they were in bad shape, The car ran great for about 10 minutes untill it heated up again and then it died, Even if trying to floor the car it wont stay running. Im Gonna try and drain the gas one of these days i have more time, im unsure what to do with 10+ gallons of gas, but ill find a home for it. Since i did the plugs, and wires i am no longer getting a misfire on cylinder 2. Next time i get the car running decent, i will try to disconnect the maf to see if the car acts similair to when it dies. If it was maf, or iac wouldn't it sooner or later throw that code again? After gas, im out free ideas... How much are the maf's for these cars, and where can i get the special tool needed to remove it? I Dont mind spending money on the car, but really dont want to buy stuff, or do things to it unless i absolutly need it. thanks, Chris

BNaylor
03-20-2007, 06:01 PM
You can check for water in the fuel tank by removing the fuel filter and inspecting the residual fuel drained off. Use a container to catch it.

Have you tried disconnecting the MAF sensor? It should run fine without it hooked up. The PCM module detects no MAF signal and simply uses internal programmed MAF/VAF tables and other engine parameters from MAP, TPS and rpms. This is part of the diagnostics in the factory service manual.

On the crank position sensor see link below.

Click here (http://www.automotiveforums.com/vbulletin/showthread.php?t=652664)

llst
03-20-2007, 10:19 PM
The MAF sensor appears to be my problem. Started the car to let it warm up and to try and get my scan tool operating. It ran fine for ten minutes and then stalled and would not run. I disconnected the MAF sensor and restarted it and it ran okay. Reconnected the MAF and it stalled out again. Took it around the block with MAF disconnected and it seems fine.
Still can't get my AutoEnginuity to talk to my computer.

Thanks to all who suggested that and other checkfors.

Larry

Sideways240sx
03-21-2007, 03:09 PM
Maf was my problem as well. Bought a remanufactured one, put it in, car runs great. Thanks for all the help guys. Chris

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