87 Targa starts cold but takes 3, 4 sec cranks to start when hot

[Democreature]

My 1987 Targa 3.2 starts instantly when cold but takes up to 3 - 4 second cranks to start when hot.
It has never failed to start when hot just takes up 3 crank attempts to start; sometimes 4. I saw the same issue here but failed to find the thread again to review for a solution. Once it starts, it runs as normal as always. I just hate cranking it for an extended period of time. During the winter, it cranks and starts right away, the summer or warmer days is another story.

What I mean by hot is after it has run for a while. It can be 100 degrees (ambient temperature) here and still start quickly the first time after sitting all night long.

Any help, suggestions or direction would be greatly appreciated.

[steely]

I had a similar but flipped issue, difficult starting when outside temps dropped.
Mine was ICV related, but, I wonder if yours might be related to O2 sensor or CHT.
Others may chime in.

[Mony]

Have a similar issue too, waiting for others to chime in.

[john walker's workshop]

Crank attempts? Do you just crank for 3 seconds and stop/repeat? What happens when you keep cranking until it starts, like most people do?

[Democreature]

Originally Posted by john walker's workshop

Crank attempts? Do you just crank for 3 seconds and stop/repeat? What happens when you keep cranking until it starts, like most people do?

Correct, I crank for 3 seconds and repeat the process until it start which it always does. I don't do a continuous crank, that process seems to take much longer to start.

[DRACO A5OG]

It could be your starter, after a run it will get heat soaked and take longer to start.

As JW stated, keep it cranked until it starts, for extra measure push in the clutch pedal so start doesn't have to work so hard.

[Democreature]

Originally Posted by DRACO A5OG

It could be your starter, after a run it will get heat soaked and take longer to start.

As JW stated, keep it cranked until it starts, for extra measure push in the clutch pedal so start doesn't have to work so hard.

The starter cranks over like a champ. I was thinking timing or poor spark performance. Maybe a new distributor, not sure that's why I ask for input.

[pmax]

Originally Posted by Democreature

My 1987 Targa 3.2 starts instantly when cold but takes up to 3 - 4 second cranks to start when hot.
It has never failed to start when hot just takes up 3 crank attempts to start; sometimes 4. I saw the same issue here but failed to find the thread again to review for a solution. Once it starts, it runs as normal as always. I just hate cranking it for an extended period of time. During the winter, it cranks and starts right away, the summer or warmer days is another story.

Your post is confusing.

What I mean by hot is after it has run for a while. It can be 100 degrees here and still start quickly the first time.

Any help, suggestions or direction would be greatly appreciated.

Does it still start when hot even during the colder months ?

[Democreature]

Originally Posted by pmax

Your post is confusing.



Does it still start when hot even during the colder months ?

During the colder months, it starts normally or within the first crank. When I drive for and hour (during the cold months) and it sits for half an hour or less, it starts as normal. It's only when it's been driven during the hotter months that the issue arises.

[rick-l]

Do you have an Ohm meter? You could check the Cylinder Head Temperature sensor.

[darrin]

had a similar issue when my DME relay was failing, it would turn over quite quickly but would initially not show any "interest" in starting, but then would fire right up.

Replacing the DME relay solved my issue (its cold soldier joints eventually passed current) -- identified issue by tapping the DME relay while cranking - tapping would trigger a start. Have you tried replacing your DME relay yet?

[Democreature]

Originally Posted by darrin

had a similar issue when my DME relay was failing, it would turn over quite quickly but would initially not show any "interest" in starting, but then would fire right up.

Replacing the DME relay solved my issue (its cold soldier joints eventually passed current) -- identified issue by tapping the DME relay while cranking - tapping would trigger a start. Have you tried replacing your DME relay yet?

I have, that was the first thing I though it was. New, Old do the same thing.

[Democreature]

I was leading toward cam/crank sensors. I'll check the CHT sensor and report back.

[GeorgeK]

Over rich condition does that. Leaking injectors? Bad fuel pressure regulator, bad idle control valve?
You need more solid data before buying parts. Does it smell of fuel from the exhaust when it starts? Does the ICV click when you turn tbe ignition on?

[Democreature]

Originally Posted by Guest3416

Over rich condition does that. Leaking injectors? Bad fuel pressure regulator, bad idle control valve?
You need more solid data before buying parts. Does it smell of fuel from the exhaust when it starts? Does the ICV click when you turn tbe ignition on?

I does not smell like fuel, had the pump replaced within the last few months. Pressure was within specs according to the shop. ICV clicks, bad idle valve never checked.

If the cars sits for hours in the hottest of days, it will start right up but if I run it for ten minutes then stop it, that's when the delay in starting happens.

[dentist90]

Sounds like vapour lock. If fuel pressure is not maintained when shut down the heat from the engine can cause fuel to vaporize in the lines and cause difficult restarting. Check valve at fuel pump may be failing or perhaps a fuel injector is not closing fully. Testing for residual fuel pressure after shut down would be a good place to start.

[Democreature]

Originally Posted by dentist90

Sounds like vapour lock. If fuel pressure is not maintained when shut down the heat from the engine can cause fuel to vaporize in the lines and cause difficult restarting. Check valve at fuel pump may be failing or perhaps a fuel injector is not closing fully. Testing for residual fuel pressure after shut down would be a good place to start.

I had the pressure tested, the shop said it was within limits. No fuel injector failing. The search continues.

[dentist90]

Pressure tested just while running, or watched after shutdown? The problem with vapour lock is not inadequate fuel pressure while cranking or running, but the gradual loss of pressure after shutdown. Maybe ask them if they checked that too..

[Democreature]

Originally Posted by dentist90

Pressure tested just while running, or watched after shutdown? The problem with vapour lock is not inadequate fuel pressure while cranking or running, but the gradual loss of pressure after shutdown. Maybe ask them if they checked that too..

The pressure was checked before, during and after; all within specs. They were thinking electrical, they are not a Porsche Shop.

[pensacola mike]

I also was experiencing this problem with my 87 Carrera, after I changed my high pressure fuel line the starting issue was no longer a problem and my car starts with a twist of the key.