91 DX Wirinng to EGR question
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91 DX Wirinng to EGR question
Hello everyone.
I bought my first 91 civic Dx 4 speed sometime ago and I have slowly been working on minor mechanical details, the basics to be exact. I have a tad bit of mechanical knowledge until I came across the arrows in the picture. I think I am missing a purge solenoid the hoses. My EGR is unplugged and the hose for that is missing to. I thought it was simple just plug in and play but the wiring for that has been redirected to an O2 sensor and temp sensor. Pretty sure this isn’t suppose to be like this. This could be a dumb question, but is this why my car is running rich, bad exhaust smell, and sometimes it will slight choke when accelerating? Thanks for all help.
Re: 91 DX Wirinng to EGR question
Check and see which ECU you have and report back. You may have an ECU that isn't looking for an EGR valve. A previous owner may have swapped in an EGR equipped intake manifold because that's all they could find...I've seen it before. If the ECU isn't looking for the EGR system, then there is no harm in it being there and being unplugged. Are you in California, where EGR is required?
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Re: 91 DX Wirinng to EGR question
That makes a lot sense why there’s no check engine light on. I do live in California. Could this be why there’s a heavy exhaust smell in the car? I’ll check the ECU and report back. Thanks for the info.
Last edited by haku17199; Feb 14, 2018 at 12:58 PM.
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Re: 91 DX Wirinng to EGR question
I finally got some to time to check the car and it has a PM9 ECU. It seems as though I really didn’t my research right either. I missed the fact that the car has a D15B7. Could this be the issue?
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Re: 91 DX Wirinng to EGR question
The EGR is only active on deceleration (high vacuum condition). A malfunctioning EGR would generally cause a lean condition if it was open during idle or running. The engine would not idle very well (or at all). If you have a rich condition, I would look else where for an issue. I would verify timing and check 02 sensor. If you don't know the history of the engine, I would also run some Seafoam through the gas as well. A rich engine leaves a lot of carbon.
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