2QUIK6

Well, I got it in, ZZ4 short block with ZZ4 cam.
Stabbed the distributor in with the timing mark at TDC on the compression stroke on #1 cyclinder. Rotor was pointing more towards the #3&5 cyclinder, not straight at #1, but made sure the #1 terminal on the rotor cap was right even with the rotor. (Does this matter that it wasn't pointing at #1 as long as the #1 terminal on the cap is even with the rotor?)
Engine started right up after a few tries and advancing the rotor just a little counter clock wise.
Ran it for 20 minutes at around 2k RPMs and as I let off the throttle after 20 minutes, it began idling rough and back fired a little thru the intake and died.
Couldn't hardly get it to run after that without back firing thru the intake , the timing was way advanced, like past 25 degrees, I moved it back down but it continued to backfire worse.
When I unplug the green wire to the MAP to set base timing, I can barely keep it running.
I've managed to get it to idle and run good in "park" with about 8-10 degrees of base timing advance, very eratic.
In gear it continues to run but can't do more than 15 mph, has no power at all.
Hooked up a vacuum gauge, it pulls a constant 9-10 inches at idle (650 rpms), not eratic vacuum at all.
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Any ideas?? Thanks for any suggestions.

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Rob
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u r sofa king we tah did

remove the number one spark plug and put your finger over the hole. have someone turn the engine over with the crankshaft bolt until you feel compression with your finger. when you start to feel it, turn the engine until the timing mark on the balancer is on 0 degrees mark. then put your distributor in and make sure it is pointing at the number 1 spark plug wire.

2QUIK6

That is exactly how I set the distributor in, except I can take the tops of my valve covers off and see that as the timing mark comes up to TDC, the intake and exhaust valve on #1 are still, and the exhaust is just closing on #6, ensuring that #1 is TDC on compresion.
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Now with the timing set at 0 degrees, it should run ok right, maybe not run as strong as it should, but it should run with no problems??
Any other ideas? I'm thinking that maybe some of the lifters have not pumped up fully yet and the exhaust valve is not opening fully yet.

[This message has been edited by 2QUIK6 (edited September 21, 2001).]

diesel

Are you sure that the timing chain is timed correctly? Engine should pull more like 17 or so inches of mercury at idle, mistimed valves will cause the vaccum to be lower (like it is in your case). My friend had the same type of problem on a F*rd M*st*ng, and he thought that it was all electronic, turns out that it was the timing chain off one tooth the whole time. I would really look at timing chain, especially since that this is a recently assembled engine.

Diesel

Rob P

iTrader: (1)

Sometimes you have to take a long screwdriver and move the oil pump shaft to allow the distributor to line up correctly. Everytime I pull the distributor in my ZZ4 it seems to move the oil pump shaft and I have to realign it (shaft) to get the distributor back in properly.

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Rob P
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2QUIK6

Well after taking off this plastic cover on my firewall which covers all of the wiring harness I discovered a second wire behind it to disconnect the ECM from adjusting the timing. I have no idea what the wire goes to that I thought was to the distributor. Anyway, now that I discovered the right wire, I found that my base timing was about 20 degrees past TDC, adjusted it to 6 and now she runs a lot better, but needs lots of tuning after she broke in.
Thanks

firbird

hey did you set the iac right let it completly close? i had the same problem when i was setting the iac i did not let it have enough time for it would close and it would have the same problem as you, when in idle it doesn not want to go over 2500 rpm and it would backfire all the time and could not go over something like 20 mph and if i tried it would backfire thought the intake and die.
i dont know i am just talking from expeniance i just got finished fixing that problem not too long ago, you might just want to take a nother look at it to see if you set it right.