1998 chevy express will not fire. sometimes it will fire after you shut key off
Year : 1998
Make : Chevrolet
Model : express
Engine : 4.3
performed multiple tests to coil, icm, ckp sensors also replaced coil ,crank sensor even tried cam position sensor. even tried web site with complete
test procedures on the named parts
Hello and Welcome to Just Answer. My name is XXXXXX XXX I will try my best to assist you and your 100% satisfaction is my goal. I have been working on these vehicles for over 10 years so I am very familiar with this system and how they work. However, keep in mind, that I need some solid concrete facts/evidence/clues from you in order to give you a good answer about your vehicle. Please realize that all my answers are based solely on the info that you provide me with.Does the check engine light come on with the key on?Does the TPS have 5 volts with the key on?
no have not checked tps
Ok.. does the engine have spark when it does not start?Are there any codes in the computer?
there is no spark at all when cranking but after turning key off sometimes you here a sizzle noise that is produced by coil and vehicle fires for a second or to
Ok.. I will do some research for you and post some information back to this page first thing in the morning. Thanks!
also i was told by another mechanic that possibly it was ecm. you can hear the fuel pump prime the crank sensor shows 5volts and 0volts. also icm trigger wire blew the bulb in test light when coil made sizzle sound but it did show a flash signal while cranking like it was trying to send signal to the coil really puzzled hope you can help need out of my shop thanks
Hello!Sorry for the delay! I could not sleep. Here is a test you can do to check the inputs of the ignition coil while cranking the engine over.First thing to do is check to see if the coil has power with the key in the on position. You can use a test light or a voltmeter. Next step would be to see if its getting a ground signal trigger. This is done with a test light. But only you would hook it up backwards. Hook the alligator clip of the test light and hook it to battery positive, and take the tip of the test light and touch it the signal wire of the coil. The test light should blink when cranking over the engine if its getting a signal. If you use a conventional test light, it will flicker very very dim (so look closely) if the coil is getting a signal to fire the spark.