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1990 chevy TBI ignition Problems

  
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1990 chevy TBI ignition Problems

 
bertscova bertscova
I love my Chevy Chevette! | Posts: 3 | Joined: 08/09
Posted: 08/18/09
09:46 PM

Hello everyone haven't been on in a while. Here is my situation. I just did a V8 engine swap on a 1990 Chevy astro van. I put a 1990 TBI 5.7 in place of the 1990 4.3 TBI. I am now having timing issues. Everything is hooked up (except for the O2 sensor it open header at present)its at tdc (held my thumb over the #1 spark plug hole turned it over until it blew my thumb off then manually turn it about a 1/4 inch to exact TDC) the rotor points at the number one post on the cap. When i turned it over it puffed through the TBI so I turned the distributor  clockwise about a 1/4 inch and now it spits a bright orange flame out of the headers, so i turned it back about an 1/8 of an inch but still get the flame through the exhaust not quit as big but its still does it. Does the distributor rotor need to be pointing at the number on piston (front Left of block) or can it point any direction as long as it points to the #1 plug wire on the cap while at TDC. Any help would be much appreciated  

85_trans_am 85_trans_am
I have an SS396 tatoo | Posts: 252 | Joined: 05/09
Posted: 08/18/09
10:05 PM

If the O2 sensor is not hooked up and the engine is running of a computer it might just be running rich. Put the O2 sensor in then see what happens.  

bertscova bertscova
I love my Chevy Chevette! | Posts: 3 | Joined: 08/09
Posted: 08/18/09
10:07 PM

The problem is that it will not start.  

waynep7122 waynep7122
Everything in my driveway’s a Chevy | Posts: 556 | Joined: 08/09
Posted: 08/19/09
08:18 AM

most gm TBI motors use 15 BTDC for base timing...     move set the timing mark there...  line up the tips of the pick up coil and the reluctor on the distributer shaft.. lock it there...

count the tips of the reluctor and the pick up coil.....      4, six or 8 teeth...   which distributer did you use????

does this distributer have the push on rotor??? if so.. pull the cap and rotor... take a bright flash light.. look straight down the shaft at the reluctor ...  if it is a riveted together piece ...  look closely at the center... see if the magnet is cracked...

the oxygen sensor is really needed to set fuel mixtures...   tbi systems will run without it.. but not anywhere near as well..

did all the ground wires get hooked up?????/ battery to engine.,  battery to body,  engine to ecm harness behind the thermostat,    engine to body.. usually on the back of the heads...

you might also see if it will run with the A and B jumped at the aldl connector or if it has the timing connector that you can unplug...   this takes the timing out of computer control...    


post what you find....  

bertscova bertscova
I love my Chevy Chevette! | Posts: 3 | Joined: 08/09
Posted: 08/19/09
12:39 PM

I need a good punch in the face. What i found is that i'm an idiot. The distributor was 180 off. Reset it and it started with a bump of the starter. But thanks to all who replied Grin