Has had distributor, sensor, timing chain, computer all replaced, fires once and then does nothing. Have tried everything, what is wrong with this thing..

Which engine? I assume it is the 4.3.

Which sensor was changed??

Any codes??

Has had distributor, sensor, timing chain, computer all replaced, fires once and then does nothing. Have tried everything, what is wrong with this thing..

Welcome to AF

What is wrong with it can only be answered threw proper testing?

We also need more info.
Engine and mileage and what all parts replaced?

Was the computer rebuilt or used and was it reprogramed?

Does it lose spark or fuel pressure?
Is fuel pressure up to par?
Does it start and run 2 seconds and then shut down?

Ign switch?
97 is a bad year on ign switches.

Check all power feed from ign switch to engine electrical and fuse box.
Will it run on carb cleraner?

Is any security lights or checkmengine ligjts staying on?

Any codes set?

Welcome to AF

What is wrong with it can only be answered threw proper testing?

We also need more info.
Engine and mileage and what all parts replaced?

Was the computer rebuilt or used and was it reprogramed?

Does it lose spark or fuel pressure?
Is fuel pressure up to par?
Does it start and run 2 seconds and then shut down?

Ign switch?
97 is a bad year on ign switches.

Check all power feed from ign switch to engine electrical and fuse box.
Will it run on carb cleraner?

Is any security lights or checkmengine ligjts staying on?

Any codes set?
4.3 Vortek
125,000
replaced distributor, timing chain, crank shaft sensor, computer was used, not reprogrammed
loses spark
pressure up to par
does not run at all much less than 2 seconds
will not run on carb cleaner
no lights staying on
no codes set

If no spark check all power feeds from ign switch.
Lot of parts replaced.
Have you still got old computer?
Why was it replaced?
What was bad on timing chain?

If no spark go threw the no spark repair flow chart?
Do you have a scanner to check for RPM signal in VCM?

Was dist set right?
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