changed optispark in 94 5.7 starts up but wont take throttle
Asked by piledaddy Apr 19, 2014 at 12:01 PM about the 1994 Chevrolet Camaro Z28 Coupe RWD
Question type: Maintenance & Repair
replaced plugs and wires also double checked them not missing.
also pulled left valve pan to make sure everything was at top dead center on compression could i be fighting another problem
11 Answers
Could be your throttle position sensor failing. It sends a reference signal to computer as to where the throttle is. Should be showing .5 volts at idle and smoothly climb to 4.5-5 volts at full throttle. If the signal is anything other than this or it jumps around as throttle is moved your car will not run properly.
http://autorepair.about.com/library/firing_orders/bl-fo-7066.htm -- check this out if there is a chance that the plug wires were not installed in the correct order.
Was it acting this way before you did the work on it?
the reason i changed the opti is because it wouldnt start now it starts right up but it also heats up fast. do you have to reset the computer or somethin
it dont miss like its out of time and from what i seen it could only be out 180 from changing the opti but then it shouldnt start but it heats up really fast in about 3 minutes like its out of time
http://shbox.com/1/93-94_opti.jpg -- it should only be able to go in one way with the shaft keyed like it is. Does that picture match yours?
http://ls1tech.com/forums/lt1-lt4-modifications/1169758-95-lt1-timing- while-installing-optispark.html -- check this out. It seems it can be install wrong and act like yours is. You might find some of the info on this link useful.
http://diysrc.com/1993-97-remove-and-replace-optispark-distributor- camaro-firebird/ -- here is something else that might be useful.
finally got it took it back apart turned the opti shaft 1 revelotion put it back on and it runs better than ever
That's great. Glad you got it going.
I changed my optispark on my 97 z28 lt1. Before I changed optispark it was still running but very hottt meaning backfires and random misfires. Now that I put new optispark times my timing chain correctly and put everything back on I start it up and it wants to fire up when I give it gas from throttle but when I let go of throttle it shuts right off. I don't know the cause of this please help!! Dealership on the phone and autozone people are telling me it could be my fuel pressure is low or I need a new fuel pump. The fuel pump itself hums when I turn the key. What's the cause of it?
