Ok yesterday i was driving my car and i was running great and i was going up this big hill and i had the gas pedal pressed all the way down and then all of a sudden it jumped up a gear and it really jerked and i was like ok so i kept on going for about a mile and then it started jumping with me and the RPM gage was jumping up and down and the service engine soon light came on only when the RPM's got real low and real high then it started to quit with me and it backfired with me like 3 or 4 times every time i would try to reb it up trying to keep it from quiting with me and it finally would start and you could smell it was flooded bout then i would let it set and try it again and it would run for a minute and quit so i finally had to get it towed so this morning i cranked it up and it cranked up fine then when it started to get hot a little it start to do the same as yesterday so i think it is the electric fuel pump or the electronic throttle body what do you think please i need help.

 

RS guy,

Green.

(You said "any answers will help...")

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Later,
Vader
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"Let the bodies hit the floor!"
Adobe Acrobat Reader

 

But seriously, scan the ECM to determine what the error code is for. That should be a good hint as to the source of the problem.

If you haven't scanned the ECM before, follw these easy steps:

First, you'll need to acquire a GM OBD I ECM Diagnostic Trouble Code Retrieval Tool (commonly known as a paper clip to TGO members).

With the engine and ignition turned off, locate the ALDL connector under the dash, just to the right of the steering wheel in the driver's foot well area. There should be a small rectangular cover over the access hole in the lower dash trim.



Insert a tool as described above (paper clip) into the 'A' and 'B' terminals on the ALDL connector:



WITHOUT STARTING the engine, turn the ignition to the "RUN" position. Watch the Malfunction Indicator Lamp (MIL) and it will begin to flash. This is also commonly called the "Service Engine Soon" or "SES" lamp. The first code will flash three times, and will usually be a code '12'. This is encoded by one flash of the lamp, a brief pause, then two successive flashes of the lamp. Each code will repeat three times, so you should see a "Code 12" flash three times. Any other error codes will follow in numerical order, and each code should flash three times. After all codes have been displayed three times, the "Code 12" will again flash three times, then all other codes will follow as described earlier. This cycle will continue until the jumper is removed or the ignition is turned off.

After you have made a note of all error codes, turn off the ignition and remove the jumper immediately. If you forget to remove the jumper and attempt to start the engine with it in place, you could damage the ECM. For this reason you should remove it immediately.

Once you have a note of all error codes, check this file for the decoding:

GM Error Codes.pdf.

You'll need Adobe Acrobat Reader to open/print the file.

------------------
Later,
Vader
------------------
"Let the bodies hit the floor!"
Adobe Acrobat Reader

 

Well Looks like Vader Beat me to It...First Off what size engine and fuel induction type? TPI? TBI? Since you metioned that the SES light came on i would recommend pulling the trouble codes and see what codes come up. Hopefully the trouble code will guide you in the right direction to begin repairs.

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88' IROC-Z, 350 TPI, 700-R4

[This message has been edited by mystikkal_69 (edited August 18, 2001).]

 

That is the longest sentence i've ever seen. BTW, Vader, your pic of the ALDL connector is from a Bird, but he's got a Camaro. A 90 Camaro ALDL is on the left side. (Just filling my nitpick quota for today. )

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-Dan
-1990 3.1L RS
-Mods? no
-Slow? yes
-Currently collecting parts for T5 swap

 

hey where can i get one of those GM OBD I ECM Diagnostic Trouble Code Retrieval Tool at and how much do they cost

 

------------------
-Dan
-1990 3.1L RS
-Mods? no
-Slow? yes
-Currently collecting parts for T5 swap

 

I think staples sells boxes of 500 of them for $5.99. Just bend one into a big 'U' and stick it in the upper right two terminals A and B.

 

my car acted similer and it turned out to be the cap rotor wires pluges etc, were all old and in bad need of replacing. it only acted up when wamed up.

 

CC,

Yes, that IS a long sentence. I realize the Camaros are "forward" and the Firebirds are "reverse", but I'd hate to have to buy a Camaro just to get some good photos. If you have any, it would be a big help for these posts. I really need to get a good shot of the interior, instrument cluster, firewall, relay banks, fan controls, ECM fuse, power distribution nodes, MAF setup, and battery/EVAP areas. Those seem to be the major areas where the two brothers are different.

My TA must be the red-headed stepchild. I know the '86 was the bastard-child of the breed, and the TAs are just that much different. It's almost so far removed from the core "family" that I could set up some sort of non-profit benefit foundation....

------------------
Later,
Vader
------------------
"Get UP - Drop the bombshell!"
Adobe Acrobat Reader

 

hey can any one explain about how to see the errors and how to check i got the book on the codes but tell it in more details on how to tell whick code it is please that is confusing

 

hey i just got through testing my Diagnostic Connector and it came up with code 23 for the fuel injection model and it says it is in the Manifold Air Temperature Sensor it says Poor electrical connection, open or short circuit; defective MAT Manifold Air Tempature sensor)sensor; defective ECM .....>>>>>> what should i do

 

Where did you get defective ECM from??? You don't mean code 12 do you?
My code list for code 23 says Low temperature at Manifold At Temperature Sensor or Throttle Position sensor error.
I'd check both sensors...make sure they are both plugged in and the wires aren't messed up. If they ARE plugged in....hell, i'd just replace both of them. They aren't too expensive.

------------------
-Dan
-1990 3.1L RS
-Mods? no
-Slow? yes
-Currently collecting parts for T5 swap

 

Ok, just so you got it right...

connect the two terminals... ( I assume you got this far)... you'll notice the fan kick on, as well as your guages light up, and your accessory stuff turn on... this is normal...

The MIL lamp will light up for a second, then shut off... this is normal... now you can start looking for codes...:

One flash
:short pause:
Flash : very short pause: flash
ause:
repeat...
Thats the indicator for a code 12 (get it... one flash plus two flashes gets you 12)... 12 just means that the ECM is getting a signal and is working correctly... "12" will flash by three times, followed by a long pauge and then more codes will flash in the same sequence... once all the trouble codes are done displaying, "12" will start over.

It takes a little while, but you'll get the hang of it...


Pull all the codes and come back here and tell us what they are... we can help you better from there...

(FYI, I had a bad MAT sensor, it won't cause what you're descibing... however if you want to by-pass it, it's simple, and I can help you with it... It'll at least tell you if it's bad of if you have an open or ground.)

Good luck, and let us know how it goes.


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1985 Camaro SC - 2.8L, auto.

http://www.xenodrgn.f2s.com/Frontright.jpg

 

Oh yeah, and Vader,

"If you forget to remove the jumper and attempt to start the engine with it in place, you could damage the ECM."

Totally -not- true... If you start the car with the A and B terminals connected, the car starts and enters "Field Service Mode"... the MIL lamp will flash fast when it's in Open Loop, and slow once it enters closed loop... once it enters closed loop, depending on how long the lamp is lit for each cycle you can determine if you're running rich or lean or not. (I just did this a few hours ago, so I know I'm right... of course I could have a bad ECM... so maybe not... but at least thats what my Chiltons says...)

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1985 Camaro SC - 2.8L, auto.

http://www.xenodrgn.f2s.com/Frontright.jpg

 

yes please tell me how to by-pass the MAT sensor i belive that will help some but i do think it is in the ECM or the Low temperature at Manifold At Temperature Sensor or the Throttle Position sensor error.but why wou;d the tach would be jumping racing down to 400rpm and up to 3000rpm back and forth but i am going to talk it to a person i know to get him to look at it maybe he can fix it