Hello all. I have a 1997 Sunfire SE 2.4 with the 4-speed automatic. Recently, shortly after having my a/c recharged, my Check Engine, ABS, and Brake lights lit up in the dash. They come on every time I start the car. I now have a firm brake pedal, and my a/c clutch will not engage. Sometimes, under the hood near the ABS module, I will hear a sound that sounds sort of like the old dot matrix printers. The a/c system was properly filled at the shop. All fuses have been checked and are good, and I cleaned the electrical contacts and grounds. The shop told me it must be a bad ecm or a short somewhere in the wiring. So, I replaced the ecm with another used one, and still have the same problem. All wheel speed sensors are connected. I also left the battery disconnected overnight, and that didn't help. When I pulled the codes for the Check Engine light, I only got Shift Solenoid A and Shift Solenoid B pending codes. Has anyone experienced a problem like this? I will try anything before taking it back in for diagnosis.
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sounds like a bad abs sensor to me, possibly on the master cylinder, but im not sure, might be somewhere to start though.
im guessing your CEL is related as well, since the ABS is pissed about something, its confusing your computer when it shifts. might even be a wheel sensor.
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Bump. Any more ideas? I really need this car back on the road!
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did you try any of the ideas i told you?
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Tater wrote:sounds like a bad abs sensor to me, possibly on the master cylinder, but im not sure, might be somewhere to start though.
im guessing your CEL is related as well, since the ABS is pissed about something, its confusing your computer when it shifts. might even be a wheel sensor.
Ummmm no, ABS sensor on the master cylinder, WTF are you talking about.
Having an ABS code for a speed sensor will not effect transmission shift patterns, if a vehicle has an ABS code, the ABS system is turned off until the problem is fixed
- 2004 Cavalier - 124k, owned since new
Jonesey wrote:Hello all. I have a 1997 Sunfire SE 2.4 with the 4-speed automatic. Recently, shortly after having my a/c recharged, my Check Engine, ABS, and Brake lights lit up in the dash. They come on every time I start the car. I now have a firm brake pedal, and my a/c clutch will not engage. Sometimes, under the hood near the ABS module, I will hear a sound that sounds sort of like the old dot matrix printers. The a/c system was properly filled at the shop. All fuses have been checked and are good, and I cleaned the electrical contacts and grounds. The shop told me it must be a bad ecm or a short somewhere in the wiring. So, I replaced the ecm with another used one, and still have the same problem. All wheel speed sensors are connected. I also left the battery disconnected overnight, and that didn't help. When I pulled the codes for the Check Engine light, I only got Shift Solenoid A and Shift Solenoid B pending codes. Has anyone experienced a problem like this? I will try anything before taking it back in for diagnosis.
Do you have any codes from the ABS module, sometimes one will turn on the either, on the older Fords if you had a leak in brake lines, your brake light would turn on, but so would your ABS, but the ABS wouldnt have any codes.
You say your pedal is firm, like hard to press, or you mean normal firm.
If hard to press, there is a line from the brake booster ( big black thing behind the master cylinder) to the intake, it is a vacuum line, it will cause that, make sure it is on, and has no holes in it.
Your A/C clutch doesnt engage, lots of things can cause that, either the system is low and the computer sees low pressure and isnt letting it turn on, you say it was charged up ( by whom) , you arent getting 12V to the clutch when you should, or your ground is bad.
- 2004 Cavalier - 124k, owned since new
I haven't pulled the codes from the ABS module yet; just trying to narrow things down before I have to take to a shop/dealer to get scanned. The pedal is firm as in hard to press; press the pedal lightly and it becomes hard to press. Pushing the pedal just past where it gets stiff stops the car quickly. I am going to check the vacuum line on the brake booster, and go over my wheel sensors once more. I took the car to a shop in town to get the a/c work done. They showed me what they did to try to get the a/c to kick on. They showed me the fuses were good, jumped the compressor to show it works, and showed me the readings on the high/low side, etc. They said it must be either the ecm or ground, and the ecm is no longer a possibility. So I suppose I need to go over my grounds/ inspect wiring again.
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Jonesey wrote:I haven't pulled the codes from the ABS module yet; just trying to narrow things down before I have to take to a shop/dealer to get scanned. The pedal is firm as in hard to press; press the pedal lightly and it becomes hard to press. Pushing the pedal just past where it gets stiff stops the car quickly. I am going to check the vacuum line on the brake booster, and go over my wheel sensors once more. I took the car to a shop in town to get the a/c work done. They showed me what they did to try to get the a/c to kick on. They showed me the fuses were good, jumped the compressor to show it works, and showed me the readings on the high/low side, etc. They said it must be either the ecm or ground, and the ecm is no longer a possibility. So I suppose I need to go over my grounds/ inspect wiring again.
Jump your low pressure switch, that is a good possibly of why the compressor isnt kicking on.
Your pressures are fine, and you can apply 12V to make it work, than you know your ground is good because, if it wasnt you would have to apply 12V and a ground, but you can just apply 12V for it to work.
low pressure switch, bypass/jump that, A/C clutch kicks on, there is your problem
- 2004 Cavalier - 124k, owned since new
I just adjusted the rear brakes just in case. I found no leaks while I was in there. The brake vacuum hose appeared to be good. After shutting the car off, I pulled the brake vacuum hose off of the intake, to listen for a "pop" sound indicating good pressure, and I heard nothing. However, I did the same thing with my 1995 Sunfire SE 2.2 that runs great (I have two sunfires), and didn't hear any "pop" sound coming from it either. So I don't know if the booster could be bad or not. By the way, where is the low pressure switch/how do I jump it, as you were saying Rob?
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Jonesey wrote:I just adjusted the rear brakes just in case. I found no leaks while I was in there. The brake vacuum hose appeared to be good. After shutting the car off, I pulled the brake vacuum hose off of the intake, to listen for a "pop" sound indicating good pressure, and I heard nothing. However, I did the same thing with my 1995 Sunfire SE 2.2 that runs great (I have two sunfires), and didn't hear any "pop" sound coming from it either. So I don't know if the booster could be bad or not. By the way, where is the low pressure switch/how do I jump it, as you were saying Rob?
You dont need to listen for a "pop" by removing the line, you are creating a vacuum leak, might stall out, or idle about 1200-1500 if it stays running
The low pressure switch, it will be on one of the A/C lines, usually, not always located close to the reciever drier.
It is a two wire connector, take a paperclip, bend it, put one of each ends into the connector ( not the part on the line, just want to make sure your following me here) see if the A/C operates.
Dont jam the thing in there though, you will damage the connector, all you need to do is make sure each one of the paperclip touches the metal tips you see in it
good luck
- 2004 Cavalier - 124k, owned since new
Well, I was going to work on the a/c issue, until an even bigger one came up. Rather than creating a new post with some of the same information as I posted earlier, I am just going to re-post what I just posted on Yahoo! Answers:
Hey all. I have a 1997 Pontiac Sunfire 2.4 with the 4T40E automatic transmission. Recently, the car has started having very late shifts. There is a CEL that stays on all the time, and it gives pending codes Shift Solenoid A and Shift Solenoid B. The transmission will go to, say, 5k or so rpm's before shifting each gear. Not good. If I let off the gas and just coast, then within a few seconds or so the rpm's drop back down to where they normally were when driving. However, as soon as I touch the gas again to keep the car moving at the same speed, the rpm's shoot right back up to a high level. When the car is going about 55 mph, I hear a clacking sound that sounds similar to the old playing card-in-the-bicycle-wheel. Also, when in park with the engine running, I can hear some type of grinding/clanging sound coming from the transmission. The fluid is good and at the right level. I don't know if this is related, but I think it is -- at the exact same time that the transmission started having all these problems, I realized that the brake pedal is now hard to press, and the booster and vacuum lines going to it are good. The transmission is electronically controlled, so I wouldn't think it could be a vacuum issue anyway, but still somehow possibly the tranny could be related to the brakes, possibly something electrical?. The pcm is also good as well. Could this be a TCC solenoid issue? If so, where would I disconnect it? I know from experience that bad TCC solenoids cause stalling, etc., but could it also cause problems like mine now? Could a loose drive axle cause any problems like these? I really need to figure out soon why the tranny is acting up particularly. The car ran fine until just after I replaced the head gasket/had the a/c recharged. I checked all fuses and tried to check the wires as best I could. All wheel speed sensors are plugged in like they should be. Please help!!! Need car for college/work!!!
By the way, the ABS and Brake lights remain on all the time as well. These lights came on at the same time as the transmission issues and the corresponding CEL light came on.
I can't type in cursive!
Bump.
I can't type in cursive!
