I have been having really bad rough idling with a lack of power. I did the plugs, wires, distributor cap and rotor. The idling seems the same and now I have a check engine light code 26. I also changed the pcv, grommet and breather and pcv hose.
Check engine light code 26 (1 Viewer)
- Thread starter sbrodacz
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- #2
I also cleaned the throttle body and had the battery out for 3-4 days. A new air filter. Could this be happening because the computer has to adjust? Idling is really bad I don't want to keep the truck running unless that'll solve the issue.
Code 26 is AFR. If you don't have an FSM, get one. It's indispensable. What did your old spark plugs look like when you pulled them? Did they all look similar? Have you had a mysterious loss of coolant lately? Is there any oil down in the spark plug tubes? What is the condition of your engine harness near the EGR plumbing? I found that mine had sustained heat damage and two wires were bare. An EGR valve that is cracked open at idle will cause a rough idle also.
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I was a little low on coolant but not bad. The firewall coolant hose loose like it may have been leaking. I have the phh work around and phh fire wall hoses from phhkit.com waiting to go in. I also lost a little coolant when I took the throttle body off. I added more. Spark plugs looked good just old. No oil on any of them.
I've started and turned off the truck several times and reved it. I went on a 15 minute drive and idling seems fine now. The check engine light also went off. Could it have been the ecu need to readjust?
Did you just recently replace parts or disconnect the battery? Anyway, I'm glad your issue seems to be history.
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- #6
I did. Vc gasket, air filter, cleaned the throttle body, spark plugs, wires, distributor cap, rotor, pcv and grommet. The battery was out for 4 days or so. I hope it is fixed and doesn't start up again. If it stays "fixed" times to move on to the phh, water pump, thermostat and radiator hoses. (They're fine just replacing them)
I have owned two 94's. The first one would idle poorly for several start ups after battery reconnect. The one I have now does not have this problem for some reason.
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- #8
Did it ever throw a code?
Not the one that idled slow. It's my understanding that O2 sensors can be going bad before they throw a code.
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- #10
I read mix threads on here regarding the 02 sensor and code 26. Don't said it could be the 02 sensor and others said it wasn't.
Well, if you running good now that's what matters. I was told by a very experienced auto mechanic to replace my O2 sensors after my HG blew. It is well known that coolant can contaminate them and cause erroneous signals but it's been nearly 1000 miles since my HG repair and it's running well with no codes.
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- #12
That's good. I just got the truck about a month ago. I'm just trying to get ready for a trip.
Good luck and enjoy your awesome vehicle.
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- #14
Needs some work but thank you!
i see code is back on but how os it running? i had a good smooth running truck with intermitant code 26 and 25( i think, rich or lean code). new O2 didnt help. finally REALLY cleaned both male and female ends of O2 plugs and sealed with dielectric grease. i also moved my O2 upto the PAIR location. i think that helps keep them dry but i think it was the cleaning that cured the problem. that was 20,000 miles ago. knock on wood. try a really good cleaning of the O2 conextors.
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- #18
Idle is not as rough as it was but still not right. If it was because the 02 sensor was wet I don't know how it could have gotten wet. The truck wasn't driven. Is there one or two O2 sensors on a 94?
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- #19
I was spraying a degreaser. Maybe it got on something.
Could be running better after the engine warms up? I don't know if that's what it started running better and the code went off after driving for a little while.
Could be running better after the engine warms up? I don't know if that's what it started running better and the code went off after driving for a little while.
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- #20
I am trying to think of everything. I had to remove the afm. There's a thicker washer that goes on the bolt. I could not find one. I put another washer on. It wasn't as thick but close. I don't know if that could be causing the issue?
