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Discussion Starter · #1 ·
I have a 1993 chevy Silverado, 1500, 350 engine. It has 162,000 miles on it and has been running fine until I washed under the hood (mistake). It has an oil leak which I really would like to find and fix. So, I decided to wash under the hood to help me find it. I know that is a big "no no" especially with a pressure washer. But I don't always make good choices and this is one of those times.

After I washed it I started it up and drove it home. The only thing out of the ordinary is it idled fast, 1500 RPMs, when I stopped at a light. When I got home I went inside for an hour or so, then came back out and it wouldn't start. It turns over fine, but won't start. So I got on the interweb and did some research. The plug wires aren't wet, and the distributor cap is dry. But, when I pulled off the cap, I noticed that the whole distributor was loose and turned freely.

I checked the electrical connection to the coil put it back together and the truck started right up. I drove it half a mile and it died. So I threw in the towel for the day.

I towed it to the shop where I work so I could be warm and have good light to work on it. My dad twisted the distributor back and forth a little while I cranked it. It fired right up and we drove it home no problem. It idled in the drive way for a few minutes, shut it off and it wouldn't start again.

It is getting fuel to the throttle body, and has spark. I went ahead and replaced the coil to eliminate that possibility and it still will do nothing.

I am out of ideas, and would appreciate any suggestions.
 

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Likely a bad ICM. Don't nickel and dime yourself. Get a new distributor. Plus, WD40 both coil low voltage plugs and the distributor plug.
 

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I agree with cowboytrukr, I went through a 6 month nightmare code 42 situation with my 1988 Chevy K5 Blazer, and it was here my final reason why it was happening, But I'd go for a new distributor but make sure you buy a Genuine GM built unit. The aftermarket is chock full of replacement disributor and there not worth the effort of purchasing or installing. My problem was a faulty Ignition Module. Once I took out the out unit and I installed a new set of GM premium plug wires, ignition module and a new set of GM Platinum "Rapid-fire plugs" the change immediately clear. It now runs like a different engine. 5.7 liter now really feels like I'm running a 210 HP engine. Have GM , Buy GM ! You'll thank yourself.
 

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View attachment 110673 I agree with cowboytrukr, I went through a 6 month nightmare code 42 situation with my 1988 Chevy K5 Blazer, and it was here my final reason why it was happening, But I'd go for a new distributor but make sure you buy a Genuine GM built unit. The aftermarket is chock full of replacement disributor and there not worth the effort of purchasing or installing. My problem was a faulty Ignition Module. Once I took out the out unit and I installed a new set of GM premium plug wires, ignition module and a new set of GM Platinum "Rapid-fire plugs" the change immediately clear. It now runs like a different engine. 5.7 liter now really feels like I'm running a 210 HP engine. Have GM , Buy GM ! You'll thank yourself.
i couldnt agree more. i found that out the hard way with a distributor
 

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Woah, put the brakes on! I had an old Pontiac Sunbird in Michigan. That snow was fun to drive in, but man, that snow could get into places it shouldn't. Like the top of the engine bay. Anyway, it died one day, which I had been delivering pizza for hours, and refused to start for about a week. Then, voila! I had the car in pieces trying to figure it out, but at random it started one day. No more issues. drove it for another six months and departed to the military... Not sure what family did with it from there.

Anyway, If you've got more money than me, throw an ICM and a distributor at it... If you've got another vehicle, let the truck sit for a week and let any aqua evaporate. Also, I have been driving my Saturn around with the MAP sensor unplugged. I had to put dielectric grease on the plug to the harness because when it rained hard, water would get all the way up to the MAP plug end and cause the car to stall out. It would not start until I blew all the water out of that plug. Point made?

Also, when I wash my engine bay, I ALWAYS keep my vehicles running when I do, If I spray something that doesn't like getting wet, at least it might tell me as instantaneous as I sprayed it that it didn't like it... and I can look more in that direction than anywhere else.

Also, You can investigate other things in the mean time. Check the oil for a milky look (indicator that water has got in it). (Oil filler and dip stick).
Check your spark plugs, if they're anything other than very lightly sooty with carbon or lightly whited (rich or lean, and in that order). If they're oil soaked, damaged or visible debris, an internal issue might be present.
Check your air filter, and make sure its not wet, and nothing else in the air cleaner isn't wet.
Unplug and plug back in any electrical connections (checking for wetness inside)
Check your gas gauge.
Did your dad tighten the distributor down after his adjustment?
Check your vacuum lines. You may have blown them off with the pressure washer.
++++You did say it had a high idle, usually this is vacuum related.
Poke around, but don't do anything that you don't know how to undo. And good luck.
 

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Discussion Starter · #6 ·
Update

I replaced the distributer and nothing changed. Decided to try starting fluid again even though I saw a little gas when cranking it before. Well, apparently I was wrong. It started right up with starting fluid and continued to run.

I can hear the fuel pump come on when I turn on the key, but for some reason I'm not getting fuel until the truck is running.

Any ideas?
 

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What’s your fuel pressure?
 
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Discussion Starter · #9 ·
Ok, so my fuel pressure is between 12 and 15 psi. I put a new fuel filter on too. The truck will run if it is started with starting fluid. It runs good for the most part but falls on its face when I hit the throttle. Which, makes me think it just isn't getting enough fuel.

I don't know as much as I would like to about the engine im working on. I was thinking the problem might be a bad pressure regulator, but, because this is a TBI engine I don't think it has a pressure regulator. Am I write about that? Or am I out of line? My way of thinking is that it has a vacuum sensor and the computer makes all the decisions. I'm thinking that water got in one of those connections or something.

Here is a picture of the electronics I am worried about. The problem is I'm ignorant as to what they are. I did wiggle the wire on all off these and put WD 40 on them and it started right up. But, I couldn't get it to start again.

I'm just about ready to role this thing off of a cliff. Any help would be greatly appreciated.
 

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Broke, without going back to re-read everything, the usual suspect with a wet engine is high voltage spark.
The water provides a conductive path to ground. 12 volts won't follow a wet trail; but 20,000 to 40,000 volts just loves a wet path to ground.
The problem is that as the spark is the taking this path to ground, it leaves a carbon trail; thus, when everything dries, the carbon trail is still there. And, the spark loves a carbon trail.
You get this trail from the wire down the sides of plugs and it will be all over the outside and the inside of the cap. You'll probably need a new cap.
You may be able to clean the plugs and, you need to clean/replace the wires.

EDIT: this phone is going to drive me nuts
 

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Discussion Starter · #11 ·
Broke, without going back to re-read everything, the usual suspect with a wet engine is high voltage spark.
The water provides a conductive path to ground. 12 volts won't follow a wet trail; but 20,000 to 40,000 volts just loves a wet path to ground.
The problem is that as the spark is the taking this path to ground, it leaves a carbon trail; thus, when everything dries, the carbon trail is still there. And, the spark loves a carbon trail.
You get this trail from the wire down the sides of plugs and it will be all over the outside and the information side of the cap. You'll probably need a new cap.
You may be able to clean the plugs and, you need to clean/replace the wires.

I'm pretty sure it has good spark. It starts right up with starting fluid. And runs fine after it is running. My question is why does it not get fuel when starting?
 

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Ok, I remember the fuel in a can thing, sorry, like I said I didn't go back and re-read.

Hmmmm, never had water cause a fuel delivery problem, unless the pressure knocked off a hose, or electrical connector.
 

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I think the TBI units have a FPR internal to them and some TBI's have the FPR mounted on the back. In any event look down the throttle bores with a flashlight in the TBI and see if you are getting a good shot of fuel in a nice cone spray pattern.
 

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Discussion Starter · #14 ·
If I look into the throttle bores with a flash light I can see the cone of fuel when the truck is running. But, there isn't a drop of fuel coming out when I am trying to start it.

Does that sound like a bad pressure regulator? Or something else? I don't know how water would effect that.

Also, if someone could tell me what the things are that are circled in the picture that would be great.

Could it be a bad mass air flow sensor?
 

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OK, how does this sound?

If you have a flooded (I mean flooded with gas) engine, the correct procedure is to hold gas pedal to the floor (WOT) and crank the engine to evac the fuel.
Pedal in this position, and engine being cranked, the computer thinks you want to clear a flooded engine condition and turns off the injectors so you don't add to the flooded condition.

So, it looks like the computer thinks your asking for WOT.

The throttle position sensor may be damaged, may only need to be reset.
Have you tried, now that it's dry, disconnecting the battery to reset everything?
 

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From back to front...map, egr, egr control...lastly, spark control, (if I remember right, for some reason...looking at pictures is different than looking with hands) the f
If I look into the throttle bores with a flash light I can see the cone of fuel when the truck is running. But, there isn't a drop of fuel coming out when I am trying to start it.

Does that sound like a bad pressure regulator? Or something else? I don't know how water would effect that.

Also, if someone could tell me what the things are that are circled in the picture that would be great.

Could it be a bad mass air flow sensor?
From back to front...map, egr, egr control...lastly, spark control, (if I remember right, for some reason...looking at pictures is different than looking with hands) the first 3 I have no question about though.

I would check on tps first as RayVoy says...there aren't many things that kill injection without killing spark, this is in the right line of thinking
 

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Exactly what I was going to suggest checking, Ray.

Broke, the regulator is integral to the throttle body. Since your pressure is 12+, I wouldn’t worry about it.

From the top of your picture, MAP, EGR, and IAC. There isn’t an MAF on the TBI engine. That’s the manifold pressure sensor. Idle air control handles engine idle speed.

Take an analog voltmeter and backprobe the throttle sensor. It should read about 0.45V at rest and rise smoothly to about 4.5V at WOT. Do this slowly and watch the meter for any dropouts as you go. If the meter drops or spikes at any point, the TPS is bad.

A digital gauge won’t respond quickly enough to give you an accurate picture.
 

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Just to clarify for broke...map and egr are circled IAC is partially circled with egr...
 

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Get it running like you have, close hood to almost closed, watch for sparking,and listen also, you could also unplug all connections for a bit to dry out
 
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