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What do you make of this electrical issue?

nutt7

nutt7

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Location
Ahwatukee, AZ -> JBLM, WA
350 tbi. Electric fans controlled by thermostat.

So, when I am running a/c (elec fans on) the lights dim and the idle drops. Not a big deal, I know it is taxing on the alt and battery. If I run errands (no a/c) and do a lot of engine starts and stops for an hour or so, the starter solenoid won't engage, or it takes a second to do so. When I does crank, it cranks fine. If it won't start, I can let it sit for a bit, and then it will start.

Also, when the vehicle is off, it takes forever to roll up the windows. As a test, I rolled them all up with the engine off, and I was unable to start it. I let it sit for a couple of hours and then it started fine.:confused:

What's going on? I had the alternator and battery tested, and he said the battery is at 80%, and alt is fine.

I am camping this weekend and prefer to not get stranded, so any help is appreciated!
 
jeff in co said:
How is your grounding and more specifically, your main grounding from the battery?
Click to expand...

I had similar issues, changed my grounding point and problem solved.
As far as the starter sounds like the solenoid is getting hot. I just did the commom remote solenoid, problem solved.
 
Poor grounds can cause the cranking issue also. I always like to run a ground from the battery to the engine, battery to frame & frame to engine. Then add frame to body & body to engine. That's a lot of grounds but it has always fixed any goofy issues that don't have an obvious fix.
 
When I did the fans, I checked, di-elec greased, and cleaned the grounds to the block, frame, and core support. I will recheck to see if any wiggled loose. Remote solenoid is a mod I need to do too...

Other ideas?
 
Just a note on the idle/electrical draw.

Have you measured system voltage under those conditions?

Not sure about the "early" TBI stuff (assuming yours is the stock '89) being capable of this, but the same vintage fuel injection on Camaro's was setup to bump the idle up with an AC request, as well as when the electric fans came on for normal cooling. Probably not a huge deal in your case, sounds like it doesn't bother you, but that may be something that could be fixed should you want to.

I know on my setup (TPI) if the electric fan came on immediately upon the engine starting, it would stall the engine.
 
dyeager535 said:
Just a note on the idle/electrical draw.

Have you measured system voltage under those conditions?

Not sure about the "early" TBI stuff (assuming yours is the stock '89) being capable of this, but the same vintage fuel injection on Camaro's was setup to bump the idle up with an AC request, as well as when the electric fans came on for normal cooling. Probably not a huge deal in your case, sounds like it doesn't bother you, but that may be something that could be fixed should you want to.

I know on my setup (TPI) if the electric fan came on immediately upon the engine starting, it would stall the engine.
Click to expand...

The idle bumps up, but not enough to compensate for the fans, which are from a windstar. Mine won't usually start if the fans are on, too. I haven't measured the voltage drop since I swapped out that gauge for tranny temp. I still have it, I suppose I can try that
 
W.r.t. the solenoid overheating, I've had good luck with these guys. Easier than rewiring a remote setup, IMO.

http://www.dormanproducts.com/p-3269-45629.aspx

45629-007.JPG
 
It sounds like typical hot start problems and typical chevy windows. The windows are fixed by the power window relay mod. The hot start is cured with remote solenoid, as mentioned already. You can always bang on the starter with the tire iron if it won't engage for you. All of the wire resistances go up as things get hot and that's why the problems get worse.

You might want to move control for the fan relay to a source that is hot in RUN, but not CRANK. How does it bump idle speed up? Is there a little solenoid under the throttle? Sometimes those can be adjusted. Another simple way to bump your idle is with a little vacuum solenoid. Wire it in parallel with the fans and plumb it to in front of the throttle (after the air filter) and to the intake manifold somehow. It's just vacuum lines and wire.
 
Blue85 said:
It sounds like typical hot start problems and typical chevy windows. The windows are fixed by the power window relay mod. The hot start is cured with remote solenoid, as mentioned already. You can always bang on the starter with the tire iron if it won't engage for you. All of the wire resistances go up as things get hot and that's why the problems get worse.

You might want to move control for the fan relay to a source that is hot in RUN, but not CRANK. How does it bump idle speed up? Is there a little solenoid under the throttle? Sometimes those can be adjusted. Another simple way to bump your idle is with a little vacuum solenoid. Wire it in parallel with the fans and plumb it to in front of the throttle (after the air filter) and to the intake manifold somehow. It's just vacuum lines and wire.
Click to expand...

The fans dont bump the idle up, i meant that the a/c does. I just need to make sure my thermoswitch override is off before I start it. I also might separate my fan circuits so I can run one independently depending on the situation. My dash lights are dimmer with the fans on, even at highway speeds. Also, rolling up the windows with the engine off made a "hot start" situation so I am not fully convinced it is completely heat related. I might go recreate that window-no-start situation again to be sure. (engine may have been hot at that time)
 
Can you just unplug one fan and see how it works?

I know it gets hot out your way, but for me with the (apparently) smaller LS1 fans, the single fan is enough to keep the engine cool. I suspect with AC and your heat, that wouldn't be the case in all driving conditions. The LS1 setup has two fans though, one is on a thermal switch (backup) the primary is ECM controlled.

Since AC kicks the idle up in your truck, the amount of idle increase is adjustable via the PROM. Probably a lot of work for minimal gain, but it's out there if you need it.
 
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