Information Overload - Troubleshooting random CLT noise

Fuel Supply & Ignition Systems

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luftvagon
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Information Overload - Troubleshooting random CLT noise

Post by luftvagon » Tue Apr 03, 2018 5:41 pm

I went on a 45 mile drive today in hopes of catching random misses I was having. The data recorder was running!

About 200s into the drive, I started experiencing issues, which are evident in Megalogviewer.

All of a sudden, CLT would experience bunch of noise.

It would go from 160F to 66F within next data point (50 points/s). Coincidentally, Batt V would drop down to 11.1v in the next data point.
MAT, MAP, AFR. and IGN are not changing. AFR changes after the event.

Lost Sync Count: 0
Lost Sync Reason: 0

Bad ground? If it was bad ground, I'd expect AFR, and MAP to go haywire.

Through the entire drive, voltage was going between 13.1v-11.1v. Normal? At times voltage would drop, but it would not affect CLT.

CLT just going bad?

RPM Averaging: 100
MAP Averaging: 100
CLT/IAT/BAT Averaging: 100

I can post the log file, if anyone is interested.
Last edited by luftvagon on Tue Apr 03, 2018 6:20 pm, edited 1 time in total.
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

luftvagon
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Re: Information Overload - Troubleshooting random CLT noise

Post by luftvagon » Tue Apr 03, 2018 6:14 pm

Image

In this picture, you can see that CLT went down all the way to -10F
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

luftvagon
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Re: Information Overload - Troubleshooting random CLT noise

Post by luftvagon » Tue Apr 03, 2018 6:18 pm

The log file is about 40MB.
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

Clonebug
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Re: Information Overload - Troubleshooting random CLT noise

Post by Clonebug » Tue Apr 03, 2018 7:29 pm

Did you check all your connections to the Relay board or wherever you have them connected???

Ground is the signal for most of the sensors so you might be having power issues instead since it kind of follows your voltage
fluctuation.

Unhook your fan belt and see if your voltage steadies up while idling in the shop.

First check if the oscillations are there at idle with the belt on.

It could be the alternator is sending a dirty voltage signal.

Make sure the alternator is grounded well with the little screw in the body running to the battery ground.
Stripped66 wrote:The point wasn't to argue air temps with the current world record holder, but to dispel the claim that the K03 is wrapped up at 150 HP. It's not.

luftvagon
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Re: Information Overload - Troubleshooting random CLT noise

Post by luftvagon » Tue Apr 03, 2018 7:55 pm

Hello, thanks for the quick reply. Yes - I wiggled and jiggled the entire wiring harness. No change. All microsquirt grounds are grounded at the same place.
None of the other sensors showed noise. Oscillations are there at idle too.
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

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Re: Information Overload - Troubleshooting random CLT noise

Post by luftvagon » Wed Apr 04, 2018 8:09 pm

Image

I've always had some noise coming in from IAT sensor. That's not ground noise either. That's just a bad Ford IAT sensor.
Take a look at the green line. That's the CLT. Look how normal, and smooth it looks, until it doesn't.

Maybe the heat bothers it. Maybe it's too hot for it. I got it connected to Type4 TempII probe location.

I think this is a case of sensor going bad, and battery fluctuation is just a red-herring.
Last edited by luftvagon on Thu Apr 05, 2018 6:44 am, edited 3 times in total.
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

luftvagon
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Re: Information Overload - Troubleshooting random CLT noise

Post by luftvagon » Wed Apr 04, 2018 8:19 pm

Guess the ultimate question is, has anyone seen a CLT start to fail like this?
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

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Re: Information Overload - Troubleshooting random CLT noise

Post by panel » Wed Apr 04, 2018 10:21 pm

Where is the Type4 TempII probe location actually ?
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luftvagon
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Re: Information Overload - Troubleshooting random CLT noise

Post by luftvagon » Thu Apr 05, 2018 5:53 am

#3 Cyl, on the head by the intake
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

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Re: Information Overload - Troubleshooting random CLT noise

Post by panel » Thu Apr 05, 2018 7:56 pm

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Built by Germans powered by Japanese and brought together by Canadians

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Re: Information Overload - Troubleshooting random CLT noise

Post by luftvagon » Tue Apr 17, 2018 9:53 pm

So back in the day when I wired the system I wired TPS wire into the ground directly as suggested by someone. After clipping it off, the noise on air temperature subsided.. and I have not had any issues with CLT. However, the BattV is still very jumpy.

However, this evening I had sync loss issues (#2); but I dont think its related to me cutting the TPS wire off. Now I am starting to wonder if the Hall Sensor had issues. Going to check that out tomorrow with the tooth logger.

I am powering IGN-4 coil from the same switched source as microsquirt, and I believe hall sensor is powered by the same switched source. Should I change any of this? Should I ground TPS wire?
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

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Re: Information Overload - Troubleshooting random CLT noise

Post by Clonebug » Thu Apr 19, 2018 9:22 pm

All sensor grounds are supposed to be grounded to the ECU or to a common ground shared with the ECU.

All my sensors go to the relay board which in turn go into the ECU.
TPS is three wires and they all go into the relay board.
Stripped66 wrote:The point wasn't to argue air temps with the current world record holder, but to dispel the claim that the K03 is wrapped up at 150 HP. It's not.

luftvagon
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Re: Information Overload - Troubleshooting random CLT noise

Post by luftvagon » Sat Apr 21, 2018 9:05 pm

I'm 99.99% confident wiring is good at this point. I split the harness the other day. All my sensors wires terminate to the common ground that goes to pin #20 on microsquirt. I clipped the TPS, and now soldering back on. There was no change in behavior. I'm still having random dips on the CLT to the point where it will kill the engine....

Back to my original thought... if the temperature is "dropping" that means the resistance is increasing somewhere. Which could probably be the thermo probe going out, a bad cable, or something inside of the microsquirt.
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

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Re: Information Overload - Troubleshooting random CLT noise

Post by Jadewombat » Sat Apr 21, 2018 10:40 pm

Are the ignition wires shielded (or twisted pairs)?

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Re: Information Overload - Troubleshooting random CLT noise

Post by luftvagon » Sun Apr 22, 2018 8:25 am

Ignition is by the way of IGN4, and QuadSpark. I do not believe parts of this harness are shielded.
1981 Volkswagen Vanagon Westfalia - air-cooled Type4 1970cc CV (hydraulic lifters, 42x36 valves, stock cam, microSquirt FI)
1993 Ford F-250 XL LWB Extended Cab 7.3L IDI

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