My black 94 was having some intermittent throttle response problems, I would have to give it more throttle than normal to accelerate from a stop. It was also getting much worse fuel mileage than my green 94.
Luckily before I started troubleshooting, the check engine light came on. I pulled the codes, 335, 336, and 337, all EGR/DPFE sensor codes. That would explain the performance problems if the EGR was opening at the wrong times.
I checked the EGR pipe first, as they can leak causing the codes, but the pipe is OK. Then I decided to replace the DPFE with a spare that I have.
First I removed the hood, I've done this before, it's easier to get at the DPFE that is mounted on the back of the drivers side head.
I put a blanket on the cowl area and set the hood on it, as I removed the hinge bolts. You could also just remove the hood struts and prop the hood up higher for access.
The second photo shows I unplugged the engine harness (blue) and moved it out of the way to access the DPFE, it's down in the red circled area. You can barely see it in the next photo.
Luckily, I have a spare DPFE on my spare engine, you can see it's held on with 2 small nuts, they were a little tricky removing them. I unplugged the electrical connector first and the 2 rubber tubes going to the EGR pipe after the DPFE was disconnected.
It's all back together again, no check engine light yet, but I'll have to drive it for a while to make sure that was the problem.
Luckily before I started troubleshooting, the check engine light came on. I pulled the codes, 335, 336, and 337, all EGR/DPFE sensor codes. That would explain the performance problems if the EGR was opening at the wrong times.
I checked the EGR pipe first, as they can leak causing the codes, but the pipe is OK. Then I decided to replace the DPFE with a spare that I have.
First I removed the hood, I've done this before, it's easier to get at the DPFE that is mounted on the back of the drivers side head.
I put a blanket on the cowl area and set the hood on it, as I removed the hinge bolts. You could also just remove the hood struts and prop the hood up higher for access.
The second photo shows I unplugged the engine harness (blue) and moved it out of the way to access the DPFE, it's down in the red circled area. You can barely see it in the next photo.
Luckily, I have a spare DPFE on my spare engine, you can see it's held on with 2 small nuts, they were a little tricky removing them. I unplugged the electrical connector first and the 2 rubber tubes going to the EGR pipe after the DPFE was disconnected.
It's all back together again, no check engine light yet, but I'll have to drive it for a while to make sure that was the problem.
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