88 bonneville cranks but wont start
#11
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still dead - took a few days off as my back just wouldn't bend over the hood much more for a while
everything I've tested looks good
has anyone here seen the whole computer go bad but still report a 12 code?
everything I've tested looks good
has anyone here seen the whole computer go bad but still report a 12 code?
#12
Senior Member
True Car Nut
Let'* get back to basics. When it is cranking but won't start, check to see if each spark plug is getting spark or not. Next, I know you don't have a gage, but you are going to have to check fuel pressure (key on, engine off) or you could end up spending time and money chasing this problem. Places like Autozone lend fuel pressure gages. They usually charge a deposit, but return it when you return the gage.
We need to know if this is a spark or a fuel problem.
We need to know if this is a spark or a fuel problem.
#13
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when I hook the timing light to the 3 front plugs it blinks on each
when I jumper the primer plug and push the schrader valve on the fuel line, the stream goes up more than a foot or so
starting fluid makes no diff at all
got an autozone in walking distance, but not sure if they still loan tools in callifornia
when I jumper the primer plug and push the schrader valve on the fuel line, the stream goes up more than a foot or so
starting fluid makes no diff at all
got an autozone in walking distance, but not sure if they still loan tools in callifornia
#14
Senior Member
True Car Nut
You need to check the back plugs as well. You can check the wires near the coil if that is easier to access. You only need to confirm presence of spark, not timing. I'm not sure how 1 foot vertical rise converts to PSI, but I'm thinking it should spray a lot further than that.
Find a fuel pressure gage.
Find a fuel pressure gage.
#15
Senior Member
True Car Nut
By the way, when you use a paper clip to check diagnostic trouble codes the system flashes code 12 to indicate the start or end of a diagnotic sequence. The system will flash code 12, followed by any stored codes, followed by code 12 again to indicate the end of the sequence. A single code 12 by itself indicates there are no codes stored in the ECM.
The fact you are getting spark on the front 3 cylinders leads me away from the ICM, coils, CPS, etc, and points in the direction of a fuel issue. I want you to check spark on the back 3 cylinders to further confirm this, but my guess is you will find spark. That is why I want you to get your hands on a fuel pressure gage.
The fact you are getting spark on the front 3 cylinders leads me away from the ICM, coils, CPS, etc, and points in the direction of a fuel issue. I want you to check spark on the back 3 cylinders to further confirm this, but my guess is you will find spark. That is why I want you to get your hands on a fuel pressure gage.
#16
Senior Member
True Car Nut
Harbor Freight sells a fuel pressure gage for $20.
Fuel Pressure Tester & Fuel Injection Pump Tester
If you don't have one near you they will ship it for $7.
Fuel Pressure Tester & Fuel Injection Pump Tester
If you don't have one near you they will ship it for $7.
#17
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OK, my neighbor is going to come by tomorrow to help me recheck some stuff & we'll see if we can get a fuel tester then. I'm afraid it may be a bad wire in the harness somewhere that makes conn when I unplug something to do a voltage test, but then loses conn when plugged back in - we'll try with him wiggling the harness while I test.
#18
Senior Member
True Car Nut
OK, my neighbor is going to come by tomorrow to help me recheck some stuff & we'll see if we can get a fuel tester then. I'm afraid it may be a bad wire in the harness somewhere that makes conn when I unplug something to do a voltage test, but then loses conn when plugged back in - we'll try with him wiggling the harness while I test.
I don't buy that. Hooking up a timing gun to a plug wire is not disrupting any wire connections, and when you do that it shows you are getting spark. The presence of spark rules out a lot of electrical related things and points to a problem with fuel. If I was a betting man I would bet you need a new fuel pump.
Have you ever change the fuel filter?
#19
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sorry, I didn't mean spark plugs but rather plugs for TPS and MAF sensor and IAT, Oil Pressure, etc.
I'll start completely over with checking all that stuff again while he wiggles harness.
I'll start completely over with checking all that stuff again while he wiggles harness.