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Lots of Knock!

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Well since you just added the fuel pump/hotwire,I'd start there.
Could be a fuse,relay,wire,ground,pump.
You can bypass the relay with a 12 volt jumper wire,see if the pump primes.
If not it's in the wiring,if the pump primes it's the relay.
Don't know how you ran the hot-wire but you may have melted a wire somewhere.
Tried to reply on the 8th but the site went down.
 
I dont think its the fuel pump because if i put the 87 computer in its starts fine, but with the 85 ecm it wont start. Maybe i dropped the 85 ecm and its broke:confused: I guess ill use the 87 ecm.
I appreciate all your help.
Let me know if you happen to think of something else that could cause my retarded knock problem.
 
Is there someway to check if the turbo is going without taking it off? I heard when a turbo is on its way out it will dump oil in the intake causing knock. I still have the bone stock 20 year old turbo.
Also, can a cam sensor that is adjusted wrong cause knock?
thanks
 
Hi underdogGN,

I had the same knock issues and the only item that was not fully tested or brand new in my 87 ECM, MAF and coil/ignition conversion was my the 87 MAF. I switched back to my 85 MAF and the crazy knock issue went away. Try that once you get your car running again. 87 ECM and 85 MAF, I'm going to hunt down a known good 87 MAF and hopefully that'll take care of the knock.
 
BLM looks to be at the max upper limit. (always running lean)Looks like with the INT at 127 the ECM is still in control,Look to see if the INT ever runs at the 150 limit or near it.As when they are both at 150 computer cannot correct the A/F mixture. Too bad you don't know what the O2 volt locks onto at WOT. Good Luck!
 
Hi Mike,

I'll have to switch back the 87 MAF and check the BLM and INT reading to see what happens when I start to get on it. A friend that has an 87 GN was trying to talk me into a WOT run to see what the O2s go to, but it scares me to death that when I do it that I'm going to damage the engine. The last time I tried to kick it with the 87 MAF, I aborted when I saw 15 degrees of knock on the scanmaster and my caspers audible went off. The most knock I've seen with the 85 MAF was 5 degrees which is much more comfortable. Also the knock stays at 0 pretty much all the time with the 85 MAF were I'd see knock go up and down just driving down the highway at 70 MPH.

What's the diffrerence between the 85 and 87 MAF anyway. Just been wondering?
 
Originally posted by esinger

What's the diffrerence between the 85 and 87 MAF anyway. Just been wondering?

They are calibrated different.
I would borrow the friend's 87 maf or have him try yours to see if it's good.
15 degrees of knock isn't good. :D
 
Ill just put my dads 87 MAF on my car. Can the scanmaster tell you if your MAF is bad?
Mike, what should the volts be like at WOT? I could test it but i dont think i should:p
You also said that my BLM is high and its running lean?
That could be involved with voltage correct?
 
Well,I am NO expert but the O2 volts I have run my car at are say .800-.830.People will say that is FAT.I have talked to guys that tell me they run there O2 volts on the ragged edge,say around .680-.690.(super lean,or at least getting there)Probably high .700's would still be safe. (.790)The thing that gets me is if you are running 45 LBs fuel pressure with the line OFF and the gauge is accurate why would the BLM be 150?That kind of leans me toward bad MAF or something to make the fuel lean even though its set high,like clogged injectors,plugged fuel filter.The voltage drop could cause lower fuel pressure or lower volume.I think you will get it, just be thorough and use common sense to try to eliminate some things.Don't take anything for "I KNOW this is good",cause you'll be chaseing yourself in circles.These are only suggestions and may not have anything to do with the actual problem.I am currently going to the School of hard "KNOCKS" too.Well, with my blown engine and all!HTH!
 
thanks mike, i guess ill start trying some ideas, like MAF, voltage @ WOT, Borrow my dads fuel pressure guage to see what thats like @ WOT, and all the other sudgestions. If nothing works ill just run 100 octane in it.:p
 
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