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Help with TB on my 1990

Posted: Fri Apr 29, 2011 8:28 pm
by indyyellow
OK. looking at the TB where it joins the intake from the front there are two devices bolted to the front side, one is the IAC? The other is? I pulled off the air intake hosing, TB is pretty dirty in there but I am still seeing a slight idle issue, a tiny bit up and down. Sometimes when it idles up the CEL comes on, if I goose it the idle goes back down and CEL goes out. There must be something on the TB that is not reading right?

Re: Help with TB on my 1990

Posted: Fri Apr 29, 2011 8:29 pm
by ronaconda
Pull the damned code!!! It'll tell you what's wrong!!!

Re: Help with TB on my 1990

Posted: Fri Apr 29, 2011 8:30 pm
by indyyellow
Also all the stuff on TB and TB have gaskets, if I take this stuff apart to clean or replace, do I need nw gaskets or will the old ones make it through being taken apart? If not are these gaskets still avail through dealer or any chain parts store or should I jsut by some gasket and try to save enough of the old to make one myself. Should it just be gasket or add some sealant with it?

Re: Help with TB on my 1990

Posted: Fri Apr 29, 2011 8:30 pm
by indyyellow
I have nothing to pull it with!!!

Re: Help with TB on my 1990

Posted: Fri Apr 29, 2011 8:31 pm
by indyyellow
Can you suggest a reader I might be able to BUY to read the codes? Is this OBDI?

Re: Help with TB on my 1990

Posted: Fri Apr 29, 2011 8:58 pm
by Money pit Beretta
Yes OBD1. Try a local parts store, they sometimes will get the codes for free. Any cheap code reader can do OBD1. I have an AutoXray it it's not a high end one, but it's not a low end one(they have many levels). I can watch sensors in real time and record close to 30 secounds of running data.

Re: Help with TB on my 1990

Posted: Fri Apr 29, 2011 9:08 pm
by indyyellow
Pep Boys here in Cincy pulls codes, maybe I can try them. They make it sound easy and fast but the two times I tried them it was HOURS wait.

Re: Help with TB on my 1990

Posted: Fri Apr 29, 2011 9:18 pm
by scannerman
The other piece on the throttle body with an electrical connector is the throttle position sensor.

Re: Help with TB on my 1990

Posted: Fri Apr 29, 2011 9:24 pm
by indyyellow
if I have to replace any of that stuff, do I need new paper gaskets? Appears there are some on the components.

Re: Help with TB on my 1990

Posted: Fri Apr 29, 2011 9:52 pm
by Money pit Beretta
indyyellow wrote:Also all the stuff on TB and TB have gaskets, if I take this stuff apart to clean or replace, do I need nw gaskets or will the old ones make it through being taken apart? If not are these gaskets still avail through dealer or any chain parts store or should I jsut by some gasket and try to save enough of the old to make one myself. Should it just be gasket or add some sealant with it?
Tim the O-rings on both just need to be cleaned with a paper towel and the you just need to put engine oil on them.

Re: Help with TB on my 1990

Posted: Fri Apr 29, 2011 10:03 pm
by indyyellow
ok

Re: Help with TB on my 1990

Posted: Sat Apr 30, 2011 12:26 am
by Cliff8928
indyyellow wrote:Can you suggest a reader I might be able to BUY to read the codes? Is this OBDI?
I have tons of "code readers" for the 87-93 cars...
Image

Re: Help with TB on my 1990

Posted: Sat Apr 30, 2011 1:46 am
by SuzukiGhostRider
He may not know of the paper clip trick Cliff. Alot of folks don't.

Tim, you can use a paper clip to "jump the pins" on your ALDL (your testing port under the dash) port and the CEL will flash a sequence of numbers starting with 1 flash, followed by two flashes for a code 12.

I believe there is a write up with pictures to demonstrate how for newbies on the board somewhere. If you'd rather not do that, you can generally pick up OBDI code readers at most any parts house for around $30 and they will come with instructions and a book of the code numbers and their meanings.

Yes, the two electrical devices connected to your TB are the IAC (Idle Air Control) Valve , and the TPS (Throttle Position Sensor).

Damn, this board seems to be getting a little harsh of late again, especially to novice mechanics, simply asking for advice............................

Re: Help with TB on my 1990

Posted: Sat Apr 30, 2011 4:42 pm
by indyyellow
I just ignore to the rude people that post. Thanks for you info Suzuki.

Re: Help with TB on my 1990

Posted: Sat Apr 30, 2011 7:19 pm
by ronaconda
I didn't mean to sound harsh...the first place you want to start with any trouble is finding out why the check engine light came on. And even though it went off, the code is still stored and and can help diagnose problems. The only way codes clear is by unhooking the battery.

Found a post explaining how you do the paper clip trick:

"Refer to the black plug to the lt side of the steering column under the dash..... there are 2 tiny leters on it..."A" & "B". using a paper clip bent in a "U" shapestick each end in those two holes. AND quoting from the book now..."once the terminals "A" & "B" are connected, turn the ignition to the "on" position, with the engine NOT running. At this point the "service engine soon" light should flash a code 12 three time consecutively. This should be the following sequence: "flash, pause, flash-flash, long pause, flash, pause, flash-flash, long pause, flash, pause, flash-flash." Code 12 indicates that the ECM's diagnostic system is operating properly. With the terminals still jumped, and after a long pause the next sequence of flashes should begin indicating the code present, and should sequence three times consecutively." Meaning if a a code 44 was present for a "lean O2 sensor" it would do the code 12 as described above, pause, then "flash-flash-flash-flash pause flash-flash-flash-flash, then long pause and will do it 2 more times. Code 45 for a rich O2, would be code 12 sequence of flashes, followed by (45) as in "flash-flash-flash-flash, pause, flash-flash-flash-flash-flash. then repeats two more times. 4 flashes for the number 4, followed by five flashes for the number 5. Then you go to the diag section, and find Chris's topic "TROUBLE CODES" and look to see what code you have and the answer to what it signifies."

Hope that helps.