johnu

No issues starting my 1987 when the engine is cold, but when the engine is warm, I have to depress the accelerator fully in order to start the car, otherwise it just turns over without actually starting.
Ideas?

thanks
John

MainePorsche

Auto or manual ?

johnu

Auto

Stromius

Check resistance of the Temp 2 on the waterbridge. Check each pole to ground. I measured mine today and get about 300 ohms on each pole to ground having just run and warm.

From WSM:

Degrees F Resistance-ohms
32 4.4-6.8k
59-86 1.4-3.6k
104 0.9-1.3k
140 480-720
176 250-390

MainePorsche

Then check flex plate tension and crank endplay if Temp 2 sensor checks out within specs.

http://dwaynesgarage.norcal928.org/

StratfordShark

Leaking fuel injectors common on car that age, and cause those symptoms (fuel has evaporated by time engine fully cool, or evaporates when you open throttle). There is excellent section in workshop manual on simple tests to identify fuel pressure problems, but you will need a pressure gauge to attach to test point at front of RHS injector rail

PHIL928

Definitely sounds like temp 2 failure. Make sure the wires at the connector are not shorting out.

johnu

thanks guys,
I will post my findings

John

Mongo

Leaking fuel dampers can cause this as well. Pull the vacuum lines off of them and see if fuel drips out of them. If so, the fuel dampers have to be replaced.

WallyP

Andy is correct - but check all three units (dampers & regulator); any trace of fuel in the vacuum lines shows failed diaphragm, mandatory replacement of the failed unit.

Mongo

I think you told me about that one a while back Wally. I pulled the vacuum line on the rear damper next to the regulator and was greated with a spritz of 91 octane.

Randy V

Try something easy first to rule out leaking injectors - run a tankfull of good gas with a quality fuel additive such as Rislone Double Strength through it.

Bill Ball

Leaky injector flooding has a classic pattern. Cold starts are fine. IMMEDIATE warm restarts are fine (not enough time for the leaky injector(s) to flood cylinder(s). Warm restarts after the car has sat for 10-15 minutes are very difficult. Holding the throttle wide open, as you are doing, can clear the flooding with all the extra air provided. If you wait until the engine is cold again or close to it, the gas usually evaporates and the start up is normal.

Mongo

Not to say you need injectors, but now would be a nifty time to look up some high impedence Ford 19lb injectors.

johnu

plug 'n play, or would I need to modify something?