Still hard start '86.5
#1
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Still hard start '86.5
It seems my grey auto is not quite right still First start up is always ok, idle good, and it takes about 2 seconds to catch. When hot if started within 4-5 minutes it will start, idle well, but may have an extended crank (5-7 seconds), or immediately start. If it sits longer (20 min) chances are it will not start for another 30 min. I have not changed the regulator or dampner as they held vacuum and had no fuel smell.
If the car does start the idle hunts like crazy unless gas is given to hold idle at 1500rpm for a few seconds, or if put in gear quickly it will almost die, then idle good.
What has been done: plugs, wires, injector cleaning, upper intake rebuild, rebuilt MAF, 02 sensor, new relays, timing belt/wp/coolant flush, oil/filter, trans service brakes bled. This car just passed ca smog with very good numbers. (after sitting for about 40 minutes due to no start)
What I have noticed (and my question). When key is turned to 'on' the fuel pump does not run for 2 seconds. When turned to 'start' the fuel pump runs. Also, when it was on the lift the pump has a very pronounced buzz. Possibly on its last legs?
Another quirk (or maybe my imagination) is when I try starting car after driving it seems if I release the key from start position (just a bit) the car will catch and start. (Possible bad switch?)
I have tried another set of computers in the car and there is no difference.
The wiring to cps, tps, idle control, injectors, are all good. Could the cps itself cause this no start?
Any thoughts or suggestions are apprectiated as I would like this finally sorted before the next project arrives.
If the car does start the idle hunts like crazy unless gas is given to hold idle at 1500rpm for a few seconds, or if put in gear quickly it will almost die, then idle good.
What has been done: plugs, wires, injector cleaning, upper intake rebuild, rebuilt MAF, 02 sensor, new relays, timing belt/wp/coolant flush, oil/filter, trans service brakes bled. This car just passed ca smog with very good numbers. (after sitting for about 40 minutes due to no start)
What I have noticed (and my question). When key is turned to 'on' the fuel pump does not run for 2 seconds. When turned to 'start' the fuel pump runs. Also, when it was on the lift the pump has a very pronounced buzz. Possibly on its last legs?
Another quirk (or maybe my imagination) is when I try starting car after driving it seems if I release the key from start position (just a bit) the car will catch and start. (Possible bad switch?)
I have tried another set of computers in the car and there is no difference.
The wiring to cps, tps, idle control, injectors, are all good. Could the cps itself cause this no start?
Any thoughts or suggestions are apprectiated as I would like this finally sorted before the next project arrives.
#2
Chronic Tool Dropper
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Plug a fuel pressure gauge onto the rail temporarilily, and see if the injectors are leaking down. All it takes is one, and the manifold fills with gas fumes that need to be pumped through before there's enough air for combustion. It's a simple test, and will tell you quickly if fuel is the problem.
#3
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OK..."Another quirk (or maybe my imagination) is when I try starting car after driving it seems if I release the key from start position (just a bit) the car will catch and start. (Possible bad switch?) .."
Yes a failing switch can do just that !!! The internal contacts wear and no longer complete the normal run mode when cranking in the start position..
Yes a failing switch can do just that !!! The internal contacts wear and no longer complete the normal run mode when cranking in the start position..
#4
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Would there be a difference as OP describes, depending on how long it's been since last run? His 'hard start after 5, no start after 20' description, leads me away from the ignition switch being a primary cause of these symptoms. If you have the original switch, it's probably not a bad idea to replace it as PM, of course.
#5
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Thank you dr bob and Jim, as I do have a new switch here I will change it. I have a fuel gauge test kit, and of course it has nothing close to the correct thread for fuel rail. Any suggestions?