Would an EGR delete affect a reset computer?

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CDTJ
Posts: 26
Joined: Wed Nov 09, 2011 6:03 pm
Car: 1986 720 4x4

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Okay, so I bought my dearly beloved 86 720 z24i a while back. I didn't like all of the vacuum lines, so of course, I deleted them. I was quite happy for some time, but then my water pump bearings were going out. Needless to say, it took me quite some time to take it apart and put it back together during school. So of course, I accidentally left my battery in, and it was deader than a doornail.
Finally get the new pump on, and a new battery. It's running, but doing some very funky things, like absolutely dying and then starting back up when I'm driving, and especially under load.
So I'm thinking, hmm, either fuel injection is cutting out, or spark is going out. So, I reset the computer.
After resetting the computer, it won't start at all without starting fluid. I can crank and crank, and nada. After struggling to get it started with ether, I let it idle for about 30 mins. It seems to idle wonderfully, until I shut the hood, and it dies. :wtf2:
Then again, crank and crank, nothing.
I pulled the throttle body off, cleaned the two injectors, pulled the ecu off, put it back on, and it started for a second, then went back to the same old same old.

Someone suggested a bad ground, but I just put a brand new negative battery cable on (the old one was torn and ratty, and actually 2 cables spliced into one), and used the exact same ground location as the old one. I can feel that there is a good connection. :gotme

So, my only other conclusion/stab in the dark is possibly the reset computer is going off of factory specs, which include emissions and egr? If so, why didn't it adjust when I had it idle for 30 mins? And why did it die when the hood slammed?

I'm at my wit's end, and just want to drive my truck again. I'm almost to the point of buying a JDM Import KA24e (which I was going to eventually do anyway), and say screw the z24i. Only thing holding me back is I have another project I'm working on, and would much prefer to work on them one at time instead of both at once this summer. My motorcycle doesn't help me on rainy days!


Note: The EGR is not actually deleted, just capped off. The rest however, is gone. I don't have a block off plate, or I'd toss the EGR valve quick.


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PEZi
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I am also thinking a bad ground... BUT... the problem that often comes up in these trucks that goes unnoticed is a bad fuel relay. Check there as well. Tap on it when the problem occurs, and if it fires right up when tapping on it, there ya go. May also be easy enough to just grab a new one and see if that solves it.

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CDTJ
Posts: 26
Joined: Wed Nov 09, 2011 6:03 pm
Car: 1986 720 4x4

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PEZi,

I can't thank you enough for your suggestion.

I first started looking in the book for the relay, and couldn't find where the relay was at in the engine bay. I definitely found the source of the problem; the pump wasn't pumping fuel (I unhooked the fuel line, and absolutely zero pressure and no noise from the pump when the key was on.)Then I started fooling with a few hot wires, and thought I had the problem licked. That is, until I shut the hood again. So I knew that it was a power issue, but not coming from the cable. Then I found a relay near the battery, checked it, and it was good. Then, I barely glimpsed another relay directly covered by the battery, and it all of a sudden made sense. It was the fuel relay, and when I bought a new and larger battery, I knocked it loose! And it made sense because my problems didn't start until I bought the replacement battery.
You were spot on with the relay suggestion! Thank you so much man! I wish there were some way to show my appreciation.

Long story short, you're the man!


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