Neg. backpressure and code 32 ?
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Joined: Jun 2003
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From: Ft. Branch, In.
Car: 88 formula WS6
Engine: 305 Lo3
Transmission: 700-R4
Neg. backpressure and code 32 ?
Anybody have problems with code 32 after installing 3" cat back exaust? My 88 305 TBI has a 3" c/b with a gutted cat and was wondering if the low back pressure was causing the EGR valve to operate in open loop. After monitoring a vacuum gauge while driving I noticed that while in open loop, the EGR valve is operating at all RPM's.
I was under the impression that the ECM grounded the control solinoid and didn't allow EGR operation untill the engine reached operating temp. and went into closed loop.
The problem is, when the engine goes into closed loop or close to it (according to my temp. gauge) the ECM tries to ground the EGR solinoid and cut off EGR operation. About 180* it cuts off EGR vacuum for 3 seconds and comes right back on. It will do this twice in about 10 sec. causing the SES light to come on and register code 32. I know I have the negative backpressure EGR valve and maybe the cat back was causing problems with the operation.
After the SES light comes on, it will stay on if I'm on the interstate untill I exit and stop and go a couple of times or, I pull over and shut it off and restart it and it will stay off.
After the engine warms up EGR operation is normal. All EGR componants are new and passages are clear. What drives me nuts, is the SES light being on and the fact that being emissions related the ECM is retarding my EST so I'm not going to get the max amount of spark advance and therfore fuel milage and power
will suffer.
Any suggestions? Anybody else having this problem? What can I do short of sticking a potato in one of my exaust pipes to increase backpressure. I've thought about installing a smaller orfice in the EGR valve but I'm not sure if that will accomplish anything but if I can't find any info I guess experimentation plus trial and error is my last resort~!
I was under the impression that the ECM grounded the control solinoid and didn't allow EGR operation untill the engine reached operating temp. and went into closed loop.
The problem is, when the engine goes into closed loop or close to it (according to my temp. gauge) the ECM tries to ground the EGR solinoid and cut off EGR operation. About 180* it cuts off EGR vacuum for 3 seconds and comes right back on. It will do this twice in about 10 sec. causing the SES light to come on and register code 32. I know I have the negative backpressure EGR valve and maybe the cat back was causing problems with the operation.
After the SES light comes on, it will stay on if I'm on the interstate untill I exit and stop and go a couple of times or, I pull over and shut it off and restart it and it will stay off.
After the engine warms up EGR operation is normal. All EGR componants are new and passages are clear. What drives me nuts, is the SES light being on and the fact that being emissions related the ECM is retarding my EST so I'm not going to get the max amount of spark advance and therfore fuel milage and power
will suffer.
Any suggestions? Anybody else having this problem? What can I do short of sticking a potato in one of my exaust pipes to increase backpressure. I've thought about installing a smaller orfice in the EGR valve but I'm not sure if that will accomplish anything but if I can't find any info I guess experimentation plus trial and error is my last resort~!
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