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High Humidity >>> Drivability Issues (SOLVED)

I

iHateVolvoPeople

Active member
Joined
Feb 1, 2014
Location
Midwest
SOLVED: the 740 had a crank no start when warm. It turned out to be the crank position sensor. The 240 runs funny above 85-90% humidity but only for a minute or 2. No big deal. I’ll consider this solved.

Gfs ole reliable 740 NA is a crank no start today. I hear the pumps priming but spark from the coil seems weak.

My 93 245 likes to have 0 power and appear to run on 2 cylinders sometimes when it’s super humid. Pulled cap and dried out rotor on the 240 and no change. Anything past like 1/8 throttle and it cuts out like a lack of fuel. Finally cleared itself up.

Humidity is 87% today.

Anyone else ever have issues in high humidity?


Edit: just got the 7 running. Cranked it for like 5 seconds and it started. So humid hardstarts, annoying. Not fuel pressure regulator AFAIK, just replaced.

Turned it off, won’t start again. Probably will get it home, reseat all electrical connections, and clean grounds
 
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Here’s a problem I’ve been meanin to address that may or may not be causing us issues. Both the fan relay and radio suppression relay connectors are like this. I was able to dig out all the crap you can see. So now I’m left with a clean gray connector and the female wires (as pictured here), but NOT the plastic pieces that clip into the connector. Paging Dave Barton.

I’d rather not splice into the harness if I don’t have to. I’ve never repaired something like this but it looks like I just need to get the plastic little bullet pieces, slip each wire in, and close the connector.

ls2y4nc_d.jpg


PWkrTco_d.jpg
 
What year 740? Every time stuff like that starts, I check the flywheel sensor / or hall sensor if 2.2. I've also had hidden issues at the FI grounds on the intake. They can corrode or the bolt strip out with no hint to the eye.
 
IM grounds are clean, I did a new gasket and a bunch of other stuff.

Been meaning to do the CPS, but didn’t think that was the issue. I see the tach jump when cranking and I thought that was a tell tale sign that the crank sensor was being triggered.

Lummert: dammit Lummert. Silicone hose over the wires instead of the plastic piece?
 
For the original problem, since it's running again, try popping the hood at night in a dark location and look carefully at all the ignition wires -- sometimes you can see the discharge where the coil/spark wires are damaged.
 
If you don't see anything when you check this. Use a squirt bottle of water and see if that affects it. If it does. Then you need new spark plug wires.
 
Well I cleaned all the male and female pieces on both relays, and reinstalled without the insulators. I may try to find the right piece or use silicone hose like Lummert said. For now, I will see if the problem persists.
 
Check fuse number one in the fuse panel behind the ash tray. That is the main one to the ECU. I had to replace that a few times. I finally replaced it with a 30 amp external fuse socket thing from napa.

The contacts in the fuse holder wore out so it was intermittent. Sometimes it would run, other times not.

What year is it? Did you check the codes if it's lh2.4? I see you say it has crank sensor, it will tell you if crank sensor is bad by checking the codes.

I see you also say it primes pump when you turn key, but have you taken the plastic outer part of the fuel pump relay off and looked at the solder joints? Lots of times those get cracked but you can fix them with a solder gun usually works best and a wee bit more solder. Look at the backside of the relay board where the main lugs from the switch come through.

Your pic of the connector with the dialectic grease in it you should be able to immerse that in hot water and soap to clean it. The grease is supposed to keep it from corroding. Same as like putting it on battery terminals. Then some de-oxit cleaner spray on the contacts. You can also deoxit spray your ECU connectors. Unplug it spray the plug and the ecu side.
 
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**** these stupid ass cars. They can win ****ing rally races but can't drive in the rain

I miss when it was 8F outside and 0% humidity. No problems then. Plug wires are new btw

93 5 speed wagon will be for sale soon.
 
Redwood Chair said:
Send her my serene condolences!
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Started today though after cleaning all those relay connectors for the RSR and aux fan. We?ll see if it still starts after she gets off work. Oh yeah and humidity is 95% today, temps are very quickly dropping. It was like 72F earlier and is dropping below freezing over night. Her car seems to be fine once it?s running whereas mine is just a huge pile of **** especially on coldstarts. Eventually mine will clear itself up and be fine though. Idk maybe I can get away with spinning some fuses? No really sure what that would affect. I?ve also cleaned all grounds on the 245 a while ago.
 
PromiseRing said:
**** these stupid ass cars. They can win ****ing rally races but can't drive in the rain

I miss when it was 8F outside and 0% humidity. No problems then. Plug wires are new btw

93 5 speed wagon will be for sale soon.
Click to expand...

But what plug wires did you use?
 
PromiseRing said:
If I pull the car in the garage and run the garage ac for an hour or so, that should theoretically remove a lot of the humidity, correct?
Click to expand...

That's kinda what air conditioning does Mr. collage student, but I turn my heat on cause I got money to burn....:-P
 
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