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DTMLGND
Can anyone tell me where this wire I believe is the CHT sensor wire coming from head near cylinder #3 should be connected to? It’s apparently cut and not sure where it goes. Thanks!
PaulClick to view attachment
914 Ranch
the rest of that wire should lead back to the computer. All of the wires to the FI system are white.How is the car running? There is a hole in the engine tin above #3, you see I can't tell which end of the cut you are holding. Back to the computer or to the CHT.Excuse me, I forgot where I am at. This would get much more attention in The Garage. Jeff doesn't come here very often.
DTMLGND
QUOTE(914 Ranch @ Apr 5 2019, 06:02 AM) *

the rest of that wire should lead back to the computer. All of the wires to the FI system are white.How is the car running? There is a hole in the engine tin above #3, you see I can't tell which end of the cut you are holding. Back to the computer or to the CHT.Excuse me, I forgot where I am at. This would get much more attention in The Garage. Jeff doesn't come here very often.


Thanks Joe! It's the wire coming from hole in the engine tin.
After months of troubleshooting and cleaning things up, it finally started up and started to idle for a short time(very rough, because I believe the spark plug wires were reversed on 1 & 3). It smokes a bit out of tailpipe and smells rich and varnishy as it sat for a few years. Some leaking apparent from fuel line, but not at injectors.
The other day it idled for 3-5 minutes and I tried to give it some gas and then it died and wouldn't restart. I restarted it yesterday and fired up quickly to low idle and then after a minute shut off. I pulled the plugs to see it they were wet, but they were mostly black and dry.
I'll see where a wire is 'cut' or missing on the ECU and try firing it up again. Seems like its flooding out or something.
JeffBowlsby
The other end of that single white wire should disappear into the FI wiring harness (which ultimately goes to the ECU).

It is for TS2 (head temp sensor) and its not likely that the engine will start without it connected. It will at least be full on rich...which may explain some of your other symptoms.
DTMLGND
QUOTE(JeffBowlsby @ Apr 5 2019, 02:56 PM) *

The other end of that single white wire should disappear into the FI wiring harness (which ultimately goes to the ECU).

It is for TS2 (head temp sensor) and its not likely that the engine will start without it connected. It will at least be full on rich...which may explain some of your other symptoms.

Thanks Jeff, Here’s another shot showing where the wires coming from. I cannot find a broken wire from any part of the harness wiring from the ECU. Click to view attachment
DTMLGND
QUOTE(DTMLGND @ Apr 5 2019, 03:32 PM) *

QUOTE(JeffBowlsby @ Apr 5 2019, 02:56 PM) *

The other end of that single white wire should disappear into the FI wiring harness (which ultimately goes to the ECU).

It is for TS2 (head temp sensor) and its not likely that the engine will start without it connected. It will at least be full on rich...which may explain some of your other symptoms.

Thanks Jeff, Here’s another shot showing where the wires coming from. I cannot find a broken wire from any part of the harness wiring from the ECU. Click to view attachment

****UPDATE****
Found the cut wire from the harness peeking out of the sheath!!
Reconnected and fired right up. Still a rough idle and need to dial it in. Bigger problem now is that gas/oil dripping on to headers around #3 or #4 cylinders. I’ll have to jack back up to get a better look tomorrow. Gotta let the heavy smoke clear for now!! Progress I suppose rolleyes.gif
914 Ranch
That is progress. The system likes to not have vacuum leaks and the valves adjusted. I hunt for the vacuum leaks with a squart bottle. I have caused myself so many problems just by having my hands down in the engine. So be careful and patiencet.
rjames
Hope it’s ok to ask this question on this thread: Was their two different CHT sensor connector types? I’ve seen both the one pictured here and also with a simple spade connector.
DTMLGND
QUOTE(914 Ranch @ Apr 6 2019, 03:54 PM) *

That is progress. The system likes to not have vacuum leaks and the valves adjusted. I hunt for the vacuum leaks with a squart bottle. I have caused myself so many problems just by having my hands down in the engine. So be careful and patiencet.

Thanks! Will try the spray bottle method.
ndfrigi
smoke probably from oil that dripped to the heat exchanger or if coming from tail pipe, maybe some old oil inside ur heat exchanger all the way to ur muffler. Check ur passenger side valve cover that may need new seal for the oil leak.
malcolm2
I have found that a Ho-Made smoke machine works great in finding vacuum leaks.

YouTube is your friend.

Basically a new empty paint can from Home Depot with a male hose fitting going in from your compressor. charcoal and cardboard burning in the can. a cheap regulator from Harbor Freight coming out of the can and a hose to the vacuum hoses on your engine anywhere. Throttle open or closed, but do both so the smoke goes everywhere. about 2 psi of smoke and you will find every leak in about 1 minute.
DTMLGND
QUOTE(ndfrigi @ Apr 17 2019, 11:18 AM) *

smoke probably from oil that dripped to the heat exchanger or if coming from tail pipe, maybe some old oil inside ur heat exchanger all the way to ur muffler. Check ur passenger side valve cover that may need new seal for the oil leak.

Thanks! Haven't been active on this project for a few months rolleyes.gif I'll check it out soon.
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