964 tiptronic No start, no crank
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From: Charlotte
964 tiptronic No start, no crank
Hello. seeking help for a 1991 Tip/Cab. Purchased from insurance company after a small engine fire, required a total engine and harness rebuild after the engine fire destroyed the main and DME and engine harnesses and all associated rubber/plastic hoses and other bits in engine bay.
Finally getting to the end, car is wired and engine is completed and installed.
PROBLEM to be solved: The starter does not get enough juice to crank/turn the flex-plate. see video for reference
1.Have turned engine over manually with tranny attached with good results, no binding.
2a. tested battery for voltage and load: Pass
2b. tested rebuilt starter for load and bench test. Pass. Bench test Volt drop at solenoid w remote trigger dipped to 8v but this will need to be recreated since on car volts were better.
3. cleaned all ground points and battery connections, cleaned all connections related to the starter wires 30 and 50.
4. Getting battery voltage at starter with no load
5. will check for drop in V with load while starting once my helper is available
6. Checked ground to battery to starter for continuity: Pass. Same for hot, continuity from battery to starter and starter to alternator
7. Tested crank using a remote starter switch and also with ignition key, same results, starter "pings" but does not have enough power to turn the toothed gear to spin flex-plate.
As a side note, before attempting to start I did run thru the DME troubleshooting tests that involve volts or ohms in the manual in sections 24/28 with all good results
Upon first key start attempt I did get the starter to engage and turn the engine over but no crank. With no other adjustments, now starter does not turn over engine.
Any help or suggestions on where to look next will be appreciated
-Todd in Charlotte, NC.
Finally getting to the end, car is wired and engine is completed and installed.
PROBLEM to be solved: The starter does not get enough juice to crank/turn the flex-plate. see video for reference
1.Have turned engine over manually with tranny attached with good results, no binding.
2a. tested battery for voltage and load: Pass
2b. tested rebuilt starter for load and bench test. Pass. Bench test Volt drop at solenoid w remote trigger dipped to 8v but this will need to be recreated since on car volts were better.
3. cleaned all ground points and battery connections, cleaned all connections related to the starter wires 30 and 50.
4. Getting battery voltage at starter with no load
5. will check for drop in V with load while starting once my helper is available
6. Checked ground to battery to starter for continuity: Pass. Same for hot, continuity from battery to starter and starter to alternator
7. Tested crank using a remote starter switch and also with ignition key, same results, starter "pings" but does not have enough power to turn the toothed gear to spin flex-plate.
As a side note, before attempting to start I did run thru the DME troubleshooting tests that involve volts or ohms in the manual in sections 24/28 with all good results
Upon first key start attempt I did get the starter to engage and turn the engine over but no crank. With no other adjustments, now starter does not turn over engine.
Any help or suggestions on where to look next will be appreciated
-Todd in Charlotte, NC.
Last edited by 91tip/cab; Oct 30, 2025 at 06:48 PM.
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From: New Westminster, BC
In my experience the battery voltage for a reasonably good battery (measured at the battery terminals) should be around 12.5 V with no load and should not be lower than around 10 - 11 V when starter is engaged. At 8 volts I am not surprised you are not getting it to turn over. If you can jumper another car battery to the one in the frunk, that should help get it cranking/starting.
Jim
Jim
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To clarify. Bench test Volt drop at solenoid w remote trigger dipped to 8v but this will need to be recreated since on car volts were better
Volts on battery w no load is 12.59, w key in On position dips to 12.42 and at crank/start position, volts dip to 12.03 w no crank, only a solid single “click” of the starter, but no gear spin.
At the starter, same battery voltage 12.55 no load, 12.4 at On and 11.99 at crank.
Volts on battery w no load is 12.59, w key in On position dips to 12.42 and at crank/start position, volts dip to 12.03 w no crank, only a solid single “click” of the starter, but no gear spin.
At the starter, same battery voltage 12.55 no load, 12.4 at On and 11.99 at crank.
Last edited by 91tip/cab; Oct 30, 2025 at 06:49 PM.
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Might be unrelated but I just had exactly the same symptoms with my C2 Tip. Electrical connections all checked out, grounds straps were good, new battery, DME was good, Starter Relay was good. It ended up being a dying starter. You said you have a remanufactured new starter. How confident are you that it's good?
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Might be unrelated but I just had exactly the same symptoms with my C2 Tip. Electrical connections all checked out, grounds straps were good, new battery, DME was good, Starter Relay was good. It ended up being a dying starter. You said you have a remanufactured new starter. How confident are you that it's good?
What is odd to understand is the starter operates very well on the bench, no so much once installed or hooked up to test like my video.
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OK, thanks for the additional info.
The only situation I can think of that matches your scenario is this: When you turn the ignition key to Start, the solenoid in the starter is pushing the starter gear out to the flywheel gear but it either may not be extending far enough to engage the internal contactor that energizes the motor to turn the starter gear or that internal contactor may be faulty. If you hear the motor click but not spin after you turn the key to start, this could be the issue. Other than that it could be a high resistance on the power connection at the starter (loose wire or corrosion) that is limiting the turning force on the motor or some other mechanical issue internal to the starter.
Further diagnosis would require getting under the car and measuring voltage at the starter and visually inspecting to see what is happening there.
Good luck!
Jim
The only situation I can think of that matches your scenario is this: When you turn the ignition key to Start, the solenoid in the starter is pushing the starter gear out to the flywheel gear but it either may not be extending far enough to engage the internal contactor that energizes the motor to turn the starter gear or that internal contactor may be faulty. If you hear the motor click but not spin after you turn the key to start, this could be the issue. Other than that it could be a high resistance on the power connection at the starter (loose wire or corrosion) that is limiting the turning force on the motor or some other mechanical issue internal to the starter.
Further diagnosis would require getting under the car and measuring voltage at the starter and visually inspecting to see what is happening there.
Good luck!
Jim
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Originally Posted by 91tip/cab
Appreciate the feedback. Comfortable the starter is good, not so much that the solenoid is 100%. I’m afraid a new starter may be the next step just to rule that out.
What is odd to understand is the starter operates very well on the bench, no so much once installed or hooked up to test like my video.
What is odd to understand is the starter operates very well on the bench, no so much once installed or hooked up to test like my video.
If you hear a click from the starter when you turn the key, your upstream electrical equipment most likely checks out. Your ignition key switch, your starter relay (you can change for the horn relay for example if you know that one works), your gear selector switch, your DME relay are all good. That leaves the battery which is easily tested and the ground connections. Is your transmission to chassis ground strap good? For me all that check out.
Unfortunately the starter is a pita to get to. Also note, the tip starter has a different part number than the manual. The tip starter looks different, the gear has a half dome cover while the manual starter has an open gear.
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From: Charlotte
New starter gets crank but no start.
Thanks for the help troubleshooting. So a new starter was the fix. I went w the new WOSP starter, primarily on price vs OEM new. Odd that the old refurbished starter bench-tested fine but once in action was a zero. I’d be curious if the old starter would work in another 964.
so now I get a crank but still need to resolve the no start. Getting spark to distributor, so will work thru timing and each sparkerlator to see if I can find the issue.
so now I get a crank but still need to resolve the no start. Getting spark to distributor, so will work thru timing and each sparkerlator to see if I can find the issue.
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The starter has to produce quite a bit of torque and like any electric motor, a worn starter can spin fine with no load, ie on the bench, but fail under load.
You need air, fuel, and spark for the engine to run. Are you sure you have fuel (fuel filter, fuel pump) and air? If you have a scope, you can test for pulse for the injectors to see if fuel gets delivered to the cylinder.
No spark can be due to bad coils, they do have a tendency to fail and a lot of people have upgraded to the 993 coils. The ignitors could be an issue but they rarely fail. I assume you tested your DME relay and your fuel pump is running.
There is an outside chance your alarm is acting up and the immobilizer has engaged.
You need air, fuel, and spark for the engine to run. Are you sure you have fuel (fuel filter, fuel pump) and air? If you have a scope, you can test for pulse for the injectors to see if fuel gets delivered to the cylinder.
No spark can be due to bad coils, they do have a tendency to fail and a lot of people have upgraded to the 993 coils. The ignitors could be an issue but they rarely fail. I assume you tested your DME relay and your fuel pump is running.
There is an outside chance your alarm is acting up and the immobilizer has engaged.
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No start caused by alarm maybe?
Couple of questions about my 1991 tip/cab. Wondering if alarm immobilizer is causing no start. I have the rear engine cover removed, the convertible top is removed and the dash/glove box is removed. This all was done during the restoration. I have an alarm module under passenger seat. No key fob w alarm, I only received a single key, no fob.
my question is: do any of the above components need to be installed/ connected in order to start the car? Do the doors need to be closed? Wondering if my alarm system or immobilizer is causing the no start issue? Any thoughts are appreciated.
my question is: do any of the above components need to be installed/ connected in order to start the car? Do the doors need to be closed? Wondering if my alarm system or immobilizer is causing the no start issue? Any thoughts are appreciated.
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I have a'90 Targa so your setup could be slightly different. The alarm is triggered by the contacts for the doors, frunk, engine lid, and glove box. There is no remote fob. When you lock the doors, you should get about 5 seconds of rapid blinking red light in the door ***** and then a slower blinking when the alarm is activated.
When triggered, the alarm sounds and the unit cuts power to the DME / starter relay if I remember correctly. Take a look at the wiring diagram.
When triggered, the alarm sounds and the unit cuts power to the DME / starter relay if I remember correctly. Take a look at the wiring diagram.
