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Discussion Starter · #1 ·
Hi. System don’t send DTC codes but I feel that ignition fatale during way. I think that coils are wrong. Resistance b/c is 0,7 ohm and A/spark is 3,9t ohms. Is it ok?
 

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Hi. I have original air filter and exhaust. Problem doesn’t stop engine but it hesitation. Primary coil is 0,7 ohms. 0,2 ohms higher than in service manual.
If both the same, about 0.2 variance, I'd not place a lot of faith in the exactness of the SM spec. A bud of mine bought two new coils and neither matched the spec. In the end, he had a fueling issue as the cause. looking at the plugs both rich and lean depending on where it's running in the calibration. As a guess, I'd say lean in the rpm area you are having the problem and rich below that. That rich can be from multiple restarts. Bottom line, plug reading has several flaws to really determine what's going on. Like I say, a combustion code will be thrown if the coil failed to light up the mixture. Hesitation events, it won't throw a code which leads me to most likely a low fuel pressure situation. Have you done a fuel pressure test?
Ron
 

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Discussion Starter · #7 ·
Hi.
I didn’t test a fuel pressure. Can I check it “at home”or only with special equipment? :)
Thx.
DI
 

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Hi.
I didn’t test a fuel pressure. Can I check it “at home”or only with special equipment? :)
Thx.
DI
See if you can rent a GM fuel tester that uses an R12 fitting. There's a black cover cap on the right side of throttle body base. Hook into that. 57-62 psi is normal and it should hold or a very slow drop over a minute once the pump stops. Do a couple of key on and off. Also do a running test higher rpms to see if it holds normal pressure. If pressure drops like a stone when pump stops, or reading drops with rpm, most likely you have a hole in the high pressure line inside the tank. End result is it will cause a lean condition, similar to what you are experiencing.
Ron
 

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Discussion Starter · #9 · (Edited)
Ron.
Thank you very much. I will try to find tester. I want to do it myself but how to find the hole?
R12=diameter 12 mm?
DI
 

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Ron.
Thank you very much. I will try to find tester. I want to do it myself but how to find the hole?
R12=diameter 12 mm?
DI
R12 is the fitting, commonly used on air conditioner units for Freon filling and testing. GM used it on early EFI as did Harley. The test fitting is on the right side at base of throttle body. Has a black plastic cap. Remove that and there's a schrader valve there.
Ron
 

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Discussion Starter · #11 ·
Hi.

I checked pressure. Results is 4 bar without changes for 2 minute.
Can I check something more?

Dariusz
 

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Hi.

I checked pressure. Results is 4 bar without changes for 2 minute.
Can I check something more?

Dariusz
Short of data logging the bike while riding, you might not find it if it's sensor related. I'm doubtful it is. To me, if this is still related to fueling, if it's repeatable at the same rpms. Do you have a tuner on this bike or had it tuned recently? 3-4k rpm can be a problem area for a stock tune at the best of times. You can test the tps signal voltage output with a multimeter for voltages as you slowly rotate the throttle. 3-4 k rpm can be several different places in the tps range however, depending on load. I doubt this is the problem.
Ron
 

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Discussion Starter · #14 · (Edited)
Hi.
I bought it with k&n filter, Tab slip and switched off lambda probe. I added PC3, switch on lambda but I didn’t see a difference. Now I use stock filter and exhaust.
 

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Hi.
I bought it with k&n filter, Tab slip and switched off lambda probe. I added PC3, switch on lambda but I didn’t see a difference. Now I use stock filter and exhaust.
Unhook the PC3 tuner and test it like that with stock calibration. See if it still has that problem.
Ron
 

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Discussion Starter · #19 ·
Short of data logging the bike while riding, you might not find it if it's sensor related. I'm doubtful it is. To me, if this is still related to fueling, if it's repeatable at the same rpms. Do you have a tuner on this bike or had it tuned recently? 3-4k rpm can be a problem area for a stock tune at the best of times. You can test the tps signal voltage output with a multimeter for voltages as you slowly rotate the throttle. 3-4 k rpm can be several different places in the tps range however, depending on load. I doubt this is the problem.
Ron
 

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Discussion Starter · #20 ·
Ron.
I am sorry. In text under you advise me to check voltage TPS. And I ask you for a reason because I thought that about wrong voltage inform codes.

Dariusz:)
 
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