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420A P0442 and engine rich

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Cfrakes

Proven Member
63
2
Jun 6, 2021
Idaho
So I got 2 codes one says the engine is running too rich and also the P0442. Could those both be from one cause? Also could a EGR delete cause the P0442?

I noticed very once in a while the gas pedal doesn't respond and also sometimes the car will crank right over and start up but then die instantly then stay on after the second startup.

Any ideas as to what to look into is appreciated. I have replaced the gas cap and fuel injectors already. Thanks
 
P0442 is an EVAP system air leak. Not related to the EGR which throws it's own set of codes. There's plenty of rubber vacuum hoses from the throttle body all the way back to the fuel tank. Any one of them could be leaking. It really sucked when I had to trace down that issue and ended up just deleting EVAP entirely and pulling the CEL bulb from my cluster. If you can get to use a smoke machine and automotive lift, it would be easier.

I'd say the running rich issue is not related. That sounds like a spark issue or possibly an FPR issue. It will have trouble starting if it's flooding. Notice any black smoke from the tail pipe? Any scents of gasoline while driving?
 
P0442 is an EVAP system air leak. Not related to the EGR which throws it's own set of codes. There's plenty of rubber vacuum hoses from the throttle body all the way back to the fuel tank. Any one of them could be leaking. It really sucked when I had to trace down that issue and ended up just deleting EVAP entirely and pulling the CEL bulb from my cluster. If you can get to use a smoke machine and automotive lift, it would be easier.

I'd say the running rich issue is not related. That sounds like a spark issue or possibly an FPR issue. It will have trouble starting if it's flooding. Notice any black smoke from the tail pipe? Any scents of gasoline while driving?
I have a really crappy air intake that is not even tight on the throttle could that cause a P0442? I'll be getting a stock intake here soon. No black smoke at all from the tail pipe only smell is a smell of exhaust fumes but I believe that's a hole in the exhaust
 
The vacuum for the EVAP system is pulled post throttle plate, so any issue before the throttle plate would have no effect on system functionality.
Gotcha. So check basically all the vacuum lines. I could have sworn I heard air escaping from behind the upper intake manifold but sprayed everything and I found nothing. Are there any lines that could be tucked under the intake I should check out? I also noticed that the cruise control box under the intake manifold was loose could that cause it?
 
The cruise control is run off a separate vacuum line so a leak there also would not cause your code. That black reservoir is prone to cracking open though and causing a leak. When I still had cruise control I deleted the reservoir and ran a vacuum line straight to the servo. It still functioned as intended.
 
The cruise control is run off a separate vacuum line so a leak there also would not cause your code. That black reservoir is prone to cracking open though and causing a leak. When I still had cruise control I deleted the reservoir and ran a vacuum line straight to the servo. It still functioned as intended.
Hey so It does now smell like gasoline when I am driving around like you asked. It's also having a little bit of a problem with stuttering when pushing on the gas but it goes away pretty quickly. I was going to look into my fuel pressure regulator what other things would you also recommend checking out? Thanks
 
So I have had a ruel rich in bank 1 code for a while with stuttering issues so today I decided to do a fuel pressure test and here's what I found. So just turning it to the on position got it to about 20 then I started it up with the tester plugged in and the fuel pressure was shooting rapidly from 50 to 60 back and forth. And after turning the key to on and letting it sit for a while the fuel pressure does go down. Is that a FPR or something else? Thanks. Btw this is a 420a motor
 
I'm running rich on my 98 eclipse rs ever since I replaced my fuel injectors. No leaks, and brand new fuel pump. I was thinking maybe I need to replace the FPR? If so should I just go with a stock one or something else. I'm not looking for more power by any means honestly just want good mpg. Thanks
 
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