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FIXED !!! Tii starting problem - need help

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Hi guys,

I bought a 73 tii in December. Had 2002's before, but I am pretty new to the tii world.

The car starts good when it's cold and when it's hot. But if I leave it for anywhere between 1 and 2 hours it's almost impossible to start (less than 1 hour and more than 2 hours is no problem).

I have to crank it very long, usually about 3 times for 10 sec. If I floor the gas the last time, it usually comes, but it almost sounds like it's backfiring for a few seconds, rpm's come up very slowly.

I have done a full tune-up: new plugs, wires, rotor, cap, Pertronix, valve adjustment, timing is correct (ball in the hole @ 2,500 rpm). Battery is new, starter a little older rebuilt Bosch. PO said he had the injection pump rebuilt within the last 3 years. The plugs are almost white, so I might run a little lean. But the car idles perfect and runs very good (once it is running), gas mileage between 22 and 26 mpg.

Any suggestions???

Thanks

Dieter

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I would check the cold start timer and the related senser. It sounds like you are way too rich or way too lean. A plug check would help diagnosis. G

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Check the tii register site for proper starting procedures.

You may be flooding the car if you are cranking it 3 separate times in short duration -- the cold start valve with admit gas each time you turn the key.

GL,

Ray

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If it is of any consolation, I have the same problem. Ruled out the cold start injector valve by making sure it wasn't leaking or injecting excess fuel when the engine is warm. Attached a little LED to the cold start injector contacts so I could see when and how long the valve is operated. The manual says one second minimum even when warm but mine doesn't activate when warm but still the engine acts like it is flooded.

Read here and there about others with similar problem - interested to hear what others say...

Deposits built up on the intake valves by the injectors?

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Subject to my crusty memory, the owner's manual starting procedure for a tii is something like this: Don't touch the throttle. Turn the key to start, and hold it there until the engine starts. After it starts to fire, keep cranking. If it doesn't fire smoothly after a second or two, press the throttle a small amount.

It sounds like your engine is flooded under the hard-start conditions. Next time you are in those conditions, try this: press the throttle all the way and hold it there. Turn the key to start, and hold it for 10-15 seconds. Keep holding the throttle down no matter what. Crank again if necessary. If it starts better this way, flooding is at least part of the problem.

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Thanks for the tips. I will try the suggested approaches. I have been reading many posts and different websites, but for some reason most problems seem to be in connection with a hot engine (vapor lock).

Could it be that it floods while it's sitting for an hour or so? I always start it (cold or hot) without touching the throttle, which works except for this specific time frame 1-2 hours.

Also, my fuel pump starts running as soon as I turn the ignition on (without cranking). Is that normal?

Thanks again, love this website.

Dieter

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If it's any consolation, I do recall mine having similar behavior.

I think everything has to be perfect to start a tii without drama under those conditions.

Throttle linkage and adjustment

injectors

timing and distributor advance springs and points

KF pump and cold start circuit and warm up regulator

valve adjustment

etc. ;-)

Cheers,

Ray

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Curt's post matches what I've always done on my tii's. I sometimes give the gas a quick tap on the 2nd or 3rd turnover if I'm in a hurry and it will fire right up.

Before starting the car again after the 1-2hr time period pull the boot off of the throttlebody and see if it is full of fuel as you may have a cold start injector that is having bladder problems. You may also want to try disconecting the cold start injector (on a seperate attempt) before starting (after waiting) to see if that helps. This technique may not make a difference if the cold start injector is dribbling due to it being worn out.

KC

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....yer just swatting at the flys

FUEL PRESSURE TEST GAUGE

without knowing the fuel pressure,

and output/volume in 30 seconds

into a measuring cup - yer just banging

yer head and knuckles

COMPRESSION TESTER

with low compression -

yer motor is not a motor

OIL PRESSURE TEST GAUGE

without first knowing the output

of the oil pump - yer just wasting

time

VOLT/OHM/MULTIMETER

another time saver and guess

eliminator

2002tiiKugelfischersystemwSpecs.jpg

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I doubt you have flooding issues.

Like others have said, I'd put a bet on the cold start injector or cold start relay box. Pull the airbox off and have a helper turn the key to the start position, the injector should give you one shot of fuel assuming coolant temps above 40F-50F.

I bought a used cold start relay box off the board last year, as my old one would flake out, usually on warm starts as it would not operate. On cold starts it would sometimes just stick open and keep the cold start injector running.... my car would sound like a diesel as it was not getting enough air.

A few things from the manual that really do help:

1) Let the fuel pump come up to pressure, 30 seconds, or I just wait to hear the audible pitch of the fuel pump change

2) Slight tip-in on the gas pedal while cranking

3) Stay on the starter long enough

The pure white/clean plugs tell me that you are running lean, getting your mixture correct will also help your cold starts.

At least that is what I found as I constantly moved the fuel curve. I have a wideband O2, so its not difficult for me to set the mixture.

Another point, how is your distributor? Have you verified the advance curve? As they age, the springs get soft, you'll get too much advance. This makes cold starting/cold running more difficult if the distributor is giving the motor too much advance too quick.

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Make sure the fuel return to the tank is working. Also remove sender and check for stuff in the tank....

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Thanks again, keep it coming.

I will look into all this on Saturday. Just bought a tii manual on Ebay, that will help me understand the system better.

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