Topic: Strange 22re misfire

[lowgeared]

At part throttle, no problem.  When I try to apply the gas, it misfires with a lot of backfires.  I am sure it is something simple, but I have never experienced this.  O2 sensor?  Air flow meter?  Coil?  Any help would be sweet!!

[lowgeared [OP]]

I swapped in a different coil and ignitor.  Problem solved.   

[lowgeared [OP]]

Problem is not solved.  It happens when it is at operating temp.  When its still cold no problems at all.  EGR or maybe the O2 sensor?  Any ideas post up please.

[BUBBA]

Hmmmm.Sounds like a timing issue.But since it only does it when at operating temp,I wouldn't think it would be the distributor.It may be a bad computer.Try shorting the pin in the test connector like you were going to set the timing and see what that does.The computer may be advancing the timing to much.

[BigMike]

Could be water in your distributor. When was the last time you washed your engine compartment direct with a garden hose?


You know, I have seen that a lot of people are quick to point the finger at a "faulty ECU" yet I have NEVER seen an ecu that has gremlins; some things work well and others dont, or only experiences problems at certain times/conditions.

In my experience, either the ecu works or it doesnt. If the check engine light comes on when the key hit the ON circuit before you fire it up, then troubleshoot somewhere else..... that is just my experience


I dont think a bad o2 would cause that, it would just throw the computer into limp mode, and an easy way to check if the EGR works, with the engine idling, unplug the vacuum line that leads to the top of the EGR diaphragm, and either crawl in there, or put a longer vacuum line on the EGR diaphragm, and then suck on it with your mouth while the engine is idling. You can easily create enough vacuum to operate the EGR on your own, and then engine will either sputter down to like 500 rpm or it will stall out. That means that it is not plugged up.

If you think it is stuck open, then simply unplug the same vacuum line that leads to the EGR diaphragm, plug it off so you dont have a leak, and then drive the truck around for a couple of minuets. Then quickly stop, get out, pop the hood, and compare the temperature differences on both sides of the EGR valve. With it unplugged, it should never open up, so therefore, the hot exhaust gases wont be passing through and into the intake manifold, and if you touch the EGR port that is on the intake side, then it should be the same temperature as the intake manifold itself, maybe around 100-150 degrees or so?
Of course the exhaust side of the EGR will be very hot, even if the EGR is not operating simply because of heat transfer through conductivity. It should be at least 300+ degrees there... so dont touch it for long hehehe

What about a bad spark plug wire? Or how about your engine and chassis grounds?

BigMike

[lowgeared [OP]]

Earlier this year I replaced the cap, rotor, wires, and plugs.  This just came about all of a sudden.  I swapped in a different coil and ignitor just assuming this would fix it and it didn't.  I work dark until dark so I am waiting til Saturday to check it out.  I will swap the pooter and try that.  I have a whole extra 22re parts 4x4 so swapping until I find the problem won't be a problem...just a PITA. 

[Shoyrtt]

Let me qualify my post in that I am certainly not an expert like Big Mike or most everyone on this board, but I did have a similar problem with my 22RE. One thing you may want to check is the wiring harness to the injectors. At the point where the harness ends and the individual wires extend to each of the injectors, you may develop a short. I was experiencing the problem and searched on the net and found a post where a guy used a piece of bark as a trail fix because his harness developed a short at that exact point. 20 years with that harness resting on a hot, vibrating motor might be the cause.

[BigMike]

Good point Shoyrtt, also its common for those little metal clips to pop off and get lost or for the plastic on the plug that keeps the metal clip in place to break off, and then the previous owner(s) just plug it back over the injector without the metal clip.

My buddies '86 Turbo started running like garbage. It had a bad idle and was guzzling the gas. But the power seemed good once you boosted it, it seemed to pull pretty hard, but man it idled badly. So I started playing with it, and I used a screw driver to listen to the injectors, and #4 was not working. Man I really didnt want to pull that fuel rail out and replace that injector, so I checked the plug..... yup. The metal clip was gone and the plug was cracked in half. Easy fix for an annoying problem

[lowgeared [OP]]

I am getting codes 5, 6 and 10.  Any ideas on what I can do?  I am going to replace the o2 sensor right now.  It probably has 200,000 on it anyway.   

[lowgeared [OP]]

Codes are now cleared but still has a little misfire/backfire.  I pulled all plugs and ran a compression test-it was ok.  #3 plug and wire appeared to be running a little hot.  I trimmed the sparkplug wire back a little and cleaned the plug.  I see that the three wire cable that goes from the coil/ignitor over to the manifold is hard and crusty.  Pulled back the insulation and the three wires look ok.  Now I am really confused.