Topic: 22re exhaust manifold turning red

[swillbuilt400]

Ok, so here is the story I just swapped a 22re from a wrecked 93 4wd i bought for parts into my 84 sr5.  The motor ran fine when it was first hooked up, but after driving it about 20 miles the 15 amp fuse under the hood blew so I replaced it.  After i did this the pickup runs again put the check engine light wont go off and when you drive the exhaust manifold turns red hot.  I checked the trouble codes and it gives me a code 12 (no rpm signal to ecu).  So, I replaced the computer with a spare computer I had and that didn't help so next I replaced the coil and igniter, checked timing, changed tps, and the pickup coil from the distributer to the igniter and nothing is making the check engine light go away or stopping the manifold from turnig red.  Any new ideas or help would be greatly appreciated.


Thanks

[Willy Mammoth]

Sounds like a timing issue. Either cam on ign timing is retarded. As for codes and computer stuff I have no ideas.

Something else that would cause a the manifold to get hot is the exhaust being restricted. Maybe the cat is plugged up?

I am sure there are others here that have had a problem like this that can help.

[bluetoy84]

This seems to be a common problem with 22re's, and nobody seems to know why. I had the same problem a couple months ago on my '89. I absolutely drove myself crazy trying to figure it out. I changed everything I could think of and nothing helped. I searched the internet for days, talked to every mechanic I knew, called and talked to LC engineering, and I tried everything they told me. Nothing helped.

I got so frustrated I ended up getting the entire EFI system, wiring harness and all, from a wrecked '93. It's fixed now but I still don't know for sure what was causing it.
I wish I knew what to tell you. This was by far the worst problem I have ever had with a vehicle. It's hard to fix something when you can't find out what's causing it.

If you find the cause PLEASE let us know for future reference. Good Luck.

[bluetoy84]

I just re-read your post and noticed that you put a '93 motor in an '84. Are you using the exhaust down pipe from the '93 or the '84 ? The '84 has a "double tube" down pipe and the EFI trucks have a "single tube" . When my manifold was glowing I had the "double tube" down pipe from an early model on it because the "single tube" cracked. I had the bung for the O2 sensor welded in the "Y" where the two pipes meet. This is now one of my suspects as to why mine was glowing. When I first noticed it glowing I tried it with just the open down pipe and no exhaust and the manifold would still glow, so I didn't think I had any restriction in the exhaust and was looking for a problem somewhere else. But when I put the '93 EFI on it I also put the single tube down pipe from the '93 on it and now it's fine. I'm not 100% sure that the down pipe had anything to do with it, but if you have the '84 downpipe I would get one from an EFI truck.

[TRACKER]

i had this problem before . i found 2 broken wires at mas air flow sensor plug .  try checking resistance between mas air sensor plug and ecu/ecm plugs

good luck

[swillbuilt400 [OP]]

Thanks for all the suggestions guys.  Too answer a few of your questions I used the down pipe from the 93 and there isn't a cat because we dont have emissions were I live in oregon.  I will try the mass air flow idea and I will make sure to post the solution to the problem.

[swillbuilt400 [OP]]

Well I checked my resistance at the mass air plug and computer and they all checked out ok.  Then I checked the mass air flow sensor too and it checked out.  I took willy mammoths advice on the timing and checked that again.  When I was cheching the timing with the diagnostic plug jumped it seemed to bounce between 5 and 3 degrees advanced.  But after I removed the jumper wire the timing stayed the same which I thought it was supposed to advanced to around 8 or 11 degrees.  Please correct me if im wrong, but im going to search the site to gigure out how you guys say to do the timing and if anybody has the any other ideas of were to look for the problem please feel free to give advice.