993turbo

My 92’ GTS hesitates a bit to start. Both from hot and cold. I need to push the accelerator for it to start. When I push the accelerator it starts right away...

Any pointers?

Ducman82

id check the TPS.

993turbo

Will check the TPS. Any writeups on the checking? I also have the diagnostic tool which I suppose gives me a few of the values. Wot / idle - closed or open.

Mrmerlin

Put a bottle of Techron in the gas also 6 oz of MMO and 2 oz of Startron do short drives see if it improves
also pull the vacuum line off the front damper smell for fuel
if you smell fuel then it might be time to replace the dampers and the FPR

Note the chemical concoction is less expensive to free up dirty injectors

worf928

That's what you need. Use the tool to make sure the idle switch is closed with no pressure on the throttle pedal and that the WOT switch is open.

993turbo

Connected the diagnostics.

Idle switch closes and opens as it should. So does WOT.

Will have a sniff at the vac line.

993turbo

No smell of fuel from the vac line.

The injectors were cleaned, new filters etc not very long ago. Do you think its a leaking injector issue?

worf928

If you have to press on the accelerator pedal to get it to start, that means it could be over-fueled at start-up. Potential causes off the top of my head:
- pressure dampener or regulator diaphragm broken thus allowing pressurized fuel to squirt through the vacuum lines and into the air guide (as per MrMerlin above.)
- leaking injector(s)
- wrong type of injector
- LH on the way out (if original un-rebuilt.)

Will it *never* start unless you press the go-pedal? Or does it just take longer to start if you don’t? The distinction between these two characteristics determines next steps.

993turbo

I tried tried another LH. Same issue.

If I dont press the accelerator, it will hardly start.

Injectors are the original ones.

I will take off the MAF and look for Fuel in the intake.

Taguid

Have you tried vacuum test with a mighty vac on dampers and fuel pressure regulator to see if they hold?

993turbo

Did it a few months ago. Can do it again.

SeanR

Don't forget the Temp II sensor and connector. If the wires are split under the boot and touching you will get a default rich condition.

993turbo

New, like 2months ago. Both the sensor and connector. But. I have another new one on the shelf so I can easily verify it.

worf928

Does the TEMP-II trim the *cranking* injector pulse width? I thought it was fixed with the TEMP-II trimming after start.

Check the TEMP-II values at the ECU plugs to ensure no harness issues. (Directions in my inspection guide. URL in my signature.)

993turbo

Will check and verify.