okay I will try and explain best I can; first It started with a spark knock. I came to that conclusion cause it only knocks while driving past 50 mph.
So, I changed:
fuel filter
knock sensor
flushed combustion chamber
changed egr valve
map sensor
idle control valve
throttle position sensor
spark plugs
spark plug wires
O2 sensor
vacumm hoses
I still get spark knock, but at this moment my concern is the shut off. It turns over and starts fine and idles great, with van in park very slight pressure on the gas pedal van stalls and wants to cut off. With van in drive and foot on the brake and very slight pressure on gas pedal van cuts off. If I press full on the pedal in drive and foot on the brake van runs and I still get spark knock if I push on the pedal farther down.
So, the only thing I can think of being the problem is fuel pump or fuel pressure regulator. I'm not in the mood for changing that **** in less I could truly be the problem and I'm forced too.
I am getting no trouble codes with the tester I have OBD1 Bosch scanner.
Any insight on the matter will be helpful
thanks!
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Hello,
Have you looked for vacuum leaks, and tested the vacuum advance canister for leaking?
The issue with replacing everything is that without testing and diagnostics, there is tons of time and money wasted.
In this case, it would be best to cut losses, and bring it in to the shop.
At the very least, a vacuum leak test is needed. The other culprits are ignition and fuel, as you know, and pressure testing the fuel system at the engine is needed as well. Also, if the throttle body is clogged, you will get detonation from a lean mixture.
Lastly, if the ignition timing is incorrect, you can expect to have these issues as the engine will only want to run at higher RPM once out of idle.
Yes changed all vacuum hoses, I didn't in the canister though; I also, thought of replacing canister cause it's the original one I believe. I figured perhaps it's saturated by now. But don't know. I know changing things is expensive to do; however many of the parts are original and the van has been in my family since it's birth so I didn't think it would hurt before I last resort took it to a shop.
Check distributor shaft for any 'lateral' movement, there should be none! .. Set base timing according to under hood decal .. This can be done with engine cover removed while driving van and adjusting distributor until valves *just stop rattling* then check with timing light... For TBI the fuel pressure must be at least 13 psi for proper engine performance... Not 12.5 but 13 PSI... That works well for me!
Yes changed all vacuum hoses, I didn't in the canister though; I also, thought of replacing canister cause it's the original one I believe. I figured perhaps it's saturated by now. But don't know. I know changing things is expensive to do; however many of the parts are original and the van has been in my family since it's birth so I didn't think it would hurt before I last resort took it to a shop.