My girlfriend has a 98 Neon with a SOHC motor with about 140K on it. The
car was not well maintained prior to her purchasing it from what i can tell.
Needless to say with this much mileage on it, we are now getting to the
point that the lack of proper maintenance is now becoming evident.
The car shows typical symptoms of rough idle, stumbling, stalling out,
etc... After reading the puter at AutoZone, it was diagnosed as having
problems with the front oxygen sensor and the EGR system. While the front
oxygen sensor is simple enough, i pulled the vacuum line between the
"Electrical EGR Transducer" and the EGR valve and the car ran fine.
According to the Haynes repair manual that i have, this tells me that the
EGR valve is working, but something else isn't. Unfortunately, the Haynes
manual doesn't tell me how to diagnose exactly what the problem is. My
guess is that it is what Haynes refers to as the "Electrical EGR
Transducer", but i'm not certain. I know that this transducer feeds the
PCM, which also relies on other sensors.
Does anyone know of a good source of info on how to make certain that the
EET is the problem? I had already purchased an EGR valve prior to finding a
manual for the car, so i don't want to end up chasing my tail or buying
anymore unnecessary parts. Any and all help appreciated. Sean
You are not supposed to have vacuum at EGR at idle. The EGR valve is due for
replacement. now would be a good time to do it. If the transducer is bad it
will cause this problem.
I appreciate your reply. Here's some more info.
I replaced both the front oxygen sensor and the EGR valve & transducer.
Checked all hoses, ended up replacing one of them. Pulled the EGR tube and
thoroughly cleaned it. Literal chunks and long thin "flakes" of carbon came
out. Everything went back together like a dream except for when i went to
plug the harness into the EGR transducer. Turns out, the harness is bad.
One of the pins from the old transducer is literally melted into the
harness. Even with that, i was able to rig the harness together, holding it
in place with a rubber band ( !!!). Not perfect, but it seems to be
working. When i shift the harness around i.e. as if the car had hit a major
bump in the road, it is definitely making & breaking contact though. Have
to head up to the local boneyard and pull a harness and splice it onto the
Anyhow, i get it all back together and the car is purring like a kitten.
The "service engine soon" light is not lighting up, which it has done
non-stop for the last several months. Needless to say, i'm overjoyed as it
seems like the car is responding to the TLC that i've been giving it.
Grabbed the old lady and headed out onto the road for a test drive.
Everything was running good. No major problems, although i could still
sense a slight lag in acceleration. Obviously, the puter's got to adjust to
the new parts. About 4 - 5 miles down the road, the "service engine soon"
light pops up. Figure that the "rigged" harness came apart, so i pull over.
The harness is still connected and working properly, as the car runs worse
when i disconnect it. Damn.
Headed over to a local AutoZone and had one of the chuckleheads re-scan the
car. Came up with codes for the front oxygen sensor and the EGR valve.
What the ???? Explained to the guy that i had just replaced these, so he
clears all the codes on the puter for me. Jump back in and away we go.
About a mile down the road, the idiot light comes on again. Needless to
say, i'm not amused. Obviously, i need to get the harness wired up
correctly and go from there.
Any ideas / comments / suggestions / observations??? Sean
The pin does not melt it just rust off and that would cause the EGR faul
code to set but WILL NOT cause the EGR valve to stay open. If the vacuum
was at the valve at idle it was because the transducer was bad (due to
water contamination)and replace it should have made an idle differecne
Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here.
All logos and trade names are the property of their respective owners.