86 sluggish cold starts
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Joined: Aug 2010
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From: Hamilton Ontario
Here ya go Tim...tweaked it a bit since the last time you saw it.
Was running lean all of a sudden when this issue started...adjusted the tables slightly to offset....a couple of runs later its starting to lean out again?
Was running lean all of a sudden when this issue started...adjusted the tables slightly to offset....a couple of runs later its starting to lean out again?
Last edited by raiderz; Jun 24, 2012 at 08:17 AM.
Le Mans Master
Joined: Mar 2002
Posts: 5,889
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From: Castro Valley Calif.
St. Jude Donor '03 thru '26
Thx Ray, why not try bumping your second value up to 3.15 which is where we had it a few months ago; or even 3.24 which is your stock BUA bin value? Increasing these numbers will give you more initial cranking fuel........maybe that will help. From reading this thread, you're prettty sure your 9th injector is OK, right?
Thread Starter
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Joined: Aug 2010
Posts: 617
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From: Hamilton Ontario
Thx Ray, why not try bumping your second value up to 3.15 which is where we had it a few months ago; or even 3.24 which is your stock BUA bin value? Increasing these numbers will give you more initial cranking fuel........maybe that will help. From reading this thread, you're prettty sure your 9th injector is OK, right?
Not 100% sure of the cold start injector...i did ohm it...ohmed out just fine...did not test the injector any further other than unplugging the connector at the injector (no change in starting) and unplugging the cold start switch at the front of the intake (no change in starting)
Ray
8th Gear
Joined: Jun 2012
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From: Jena
Hello Ray,
my csv has also 4.6 Ohm, but there came no fuel out of the csv while cranking. So my csv is death for sure. After i changed the memcal last weekend, my problem was gone.
You can remove the screw from the csv, and remove it a little bit from the intake. And than you can look for fuel while cranking. Otherwise you can check the fuel pressure while cranking. Disconnect all injectors, connect only the csv. Pressure must drop 3 psi while cranking when the csv is ok.
Best Regards,
Frank
my csv has also 4.6 Ohm, but there came no fuel out of the csv while cranking. So my csv is death for sure. After i changed the memcal last weekend, my problem was gone.
You can remove the screw from the csv, and remove it a little bit from the intake. And than you can look for fuel while cranking. Otherwise you can check the fuel pressure while cranking. Disconnect all injectors, connect only the csv. Pressure must drop 3 psi while cranking when the csv is ok.
Best Regards,
Frank
Thread Starter
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Joined: Aug 2010
Posts: 617
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From: Hamilton Ontario
Thx Ray, why not try bumping your second value up to 3.15 which is where we had it a few months ago; or even 3.24 which is your stock BUA bin value? Increasing these numbers will give you more initial cranking fuel........maybe that will help. From reading this thread, you're prettty sure your 9th injector is OK, right?
Is there an OBD1 scanner out there that can pick up cold engine misfires, or am i just back to testing and throwing parts at it?
I might try to post of video with sound that shows how it starts up...might get a few bites that way
Thanks
Ray
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Joined: Aug 2010
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From: Hamilton Ontario
Hello Ray,
my csv has also 4.6 Ohm, but there came no fuel out of the csv while cranking. So my csv is death for sure. After i changed the memcal last weekend, my problem was gone.
You can remove the screw from the csv, and remove it a little bit from the intake. And than you can look for fuel while cranking. Otherwise you can check the fuel pressure while cranking. Disconnect all injectors, connect only the csv. Pressure must drop 3 psi while cranking when the csv is ok.
Best Regards,
Frank
my csv has also 4.6 Ohm, but there came no fuel out of the csv while cranking. So my csv is death for sure. After i changed the memcal last weekend, my problem was gone.
You can remove the screw from the csv, and remove it a little bit from the intake. And than you can look for fuel while cranking. Otherwise you can check the fuel pressure while cranking. Disconnect all injectors, connect only the csv. Pressure must drop 3 psi while cranking when the csv is ok.
Best Regards,
Frank
The pressure test sounds easy enough..i will give it a shot and post results this week if i get some time.
Im sure Cold start injector is working because when it is not plugged in...longer cranking times...but i will test the PSI anyways
Ray
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Thread Starter
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Joined: Aug 2010
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From: Hamilton Ontario
Le Mans Master
Joined: Mar 2002
Posts: 5,889
Likes: 2
From: Castro Valley Calif.
St. Jude Donor '03 thru '26
I noticed an earlier post where you said you'd calibrated the MAF & that's why I wondered about those first two entries in table one.....they're pretty important to crank fueling and staying alive (in conjunction with the IAC of course). Have you taken a look at the FSM troubleshooting flowchart? I think that's where I'd start rather than trying hit or miss attempts.
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Joined: Apr 2002
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From: Anaheim CA
It's a switch. It's either open (very high resistance) or closed (very low resistance). It should only be closed if the coolant is below 95 degrees F (and if you cranked for less than 8 seconds).
Thread Starter
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Joined: Aug 2010
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From: Hamilton Ontario
Hello Ray,
my csv has also 4.6 Ohm, but there came no fuel out of the csv while cranking. So my csv is death for sure. After i changed the memcal last weekend, my problem was gone.
You can remove the screw from the csv, and remove it a little bit from the intake. And than you can look for fuel while cranking. Otherwise you can check the fuel pressure while cranking. Disconnect all injectors, connect only the csv. Pressure must drop 3 psi while cranking when the csv is ok.
Best Regards,
Frank
my csv has also 4.6 Ohm, but there came no fuel out of the csv while cranking. So my csv is death for sure. After i changed the memcal last weekend, my problem was gone.
You can remove the screw from the csv, and remove it a little bit from the intake. And than you can look for fuel while cranking. Otherwise you can check the fuel pressure while cranking. Disconnect all injectors, connect only the csv. Pressure must drop 3 psi while cranking when the csv is ok.
Best Regards,
Frank
Whats up with that?
I will try again tonight or tomorrow morning to see if i get the same results
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From: Hamilton Ontario
will test readings warmed up in a day or so...busy at work this week.
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Joined: Aug 2010
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From: Hamilton Ontario
Race Director
Joined: Apr 2002
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From: Anaheim CA
I was (not sure of the correct word to use here) wrong, inaccurate, too vague (something like that).
I did some research on this in the shop manual and they are equally vague. The fuel section (page 6E3-C2-1) just says that the cold start injector is "...controlled by a Cold Start Fuel Injection Switch which provides a ground path for the valve during cranking...". In the wiring diagrams in the back of the FSM it shows a square box labeled "THERMO TIME SWITCH". Basically it doesn't tell us what the inside of the switch looks like.
A couple years ago I had problems in that area (the throttle body coolant lines leaked and soaked my thermo switch and the connector contacts were corroded). I replaced both the thermo switch and the connector. At that time I measured the THERMAL part of the switch at 33 ohms (purple wire referenced to ground). The TAN wire is the switch part, which should measure high resistance (switch open) or low resistance (switch closed) (referenced to ground), depending on the temperature and cranking time.
I didn't measure the cold start injector back then, but I did now: 5.8 ohms.
I did some research on this in the shop manual and they are equally vague. The fuel section (page 6E3-C2-1) just says that the cold start injector is "...controlled by a Cold Start Fuel Injection Switch which provides a ground path for the valve during cranking...". In the wiring diagrams in the back of the FSM it shows a square box labeled "THERMO TIME SWITCH". Basically it doesn't tell us what the inside of the switch looks like.
A couple years ago I had problems in that area (the throttle body coolant lines leaked and soaked my thermo switch and the connector contacts were corroded). I replaced both the thermo switch and the connector. At that time I measured the THERMAL part of the switch at 33 ohms (purple wire referenced to ground). The TAN wire is the switch part, which should measure high resistance (switch open) or low resistance (switch closed) (referenced to ground), depending on the temperature and cranking time.
I didn't measure the cold start injector back then, but I did now: 5.8 ohms.
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From: Hamilton Ontario
What about a small coolant leak at the intake...would this cause the sputtering cold starts?
I have a coolant stain on the front of the block just above the waterpump to the left...looks minor but nonetheless a little wet all the time....leaking from the intake.
Also have coolant pooling on top of the intake coming up through 2 intake bolts at the front on both sides...very minor pooling...I guess these bolts are directly over the coolant passages and did not have thread sealant applied....have not ever needed to add coolant...YET.
Cant get at the bolts to re-torque...under the runners.
Valve covers are leaking a bit of oil to the top of the intake also....will try "the right stuff" instead of gaskets when i do the valve covers. I Have felpro rubber gaskets on there now but they are starting to leak after 2 years...re-torquing the valve covers did not stop the oil leak.
So...with all this minor leakage...could this be causing my sputtering start-ups. I guess the gaskets swell up and close the gaps when heated and that's why it runs okay when warmed up??
I have sprayed brake cleaner around all the possible leak areas with no change in RPM....Gaps Could have been sealed up at that point??
I have a coolant stain on the front of the block just above the waterpump to the left...looks minor but nonetheless a little wet all the time....leaking from the intake.
Also have coolant pooling on top of the intake coming up through 2 intake bolts at the front on both sides...very minor pooling...I guess these bolts are directly over the coolant passages and did not have thread sealant applied....have not ever needed to add coolant...YET.
Cant get at the bolts to re-torque...under the runners.
Valve covers are leaking a bit of oil to the top of the intake also....will try "the right stuff" instead of gaskets when i do the valve covers. I Have felpro rubber gaskets on there now but they are starting to leak after 2 years...re-torquing the valve covers did not stop the oil leak.
So...with all this minor leakage...could this be causing my sputtering start-ups. I guess the gaskets swell up and close the gaps when heated and that's why it runs okay when warmed up??
I have sprayed brake cleaner around all the possible leak areas with no change in RPM....Gaps Could have been sealed up at that point??
Last edited by raiderz; Jun 27, 2012 at 11:14 AM.
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From: Hamilton Ontario
cold start video
video posted at you tube.
You can hear the sputtering after a clod start and a big air gasp after i revved it up from idle...almost stalled
http://youtu.be/lcvjH5kuWZs
You can hear the sputtering after a clod start and a big air gasp after i revved it up from idle...almost stalled
http://youtu.be/lcvjH5kuWZs
Last edited by raiderz; Jun 29, 2012 at 07:41 AM.
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From: Hamilton Ontario
Thanks...i always at least crack the door halfway when i run the car. There was too much outside noise at that time for the video so i kept the big door shut (2mins) and had the mandoor opened...garage is detached from the house ..30feet ..appreciate your concern though...Thanks Again