Author Topic: Engine acts like it needs a set of glow plugs.  (Read 4435 times)

Offline Skunksmash

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Engine acts like it needs a set of glow plugs.
« on: September 29, 2009, 05:09:47 pm »
I know glow plugs are only for diesels heh. But my gasoline TBI 350 in my '87 acts kinda like a diesel, in one way. When it's cold, it runs badly. Then as soon as it warms up, it runs just fine. No missfires or choppy idle or anything. But when it's cold, it runs really bad. Rough idle, low volume popping noises coming from the exhaust, a little bit of black smoke in the exhaust, some mild hesitation, all the things you could expect from an old motor. I'm sure I could fix it all with a new engine. However, as I am currently going to school and drawing unemployment, this is impossible. So i was thinking maybe I could address the things that actually cause this problem. Too bad I don't know what they are lol. Anyone here know what causes this, or maybe has a few tips/tricks I could do to cut it down? Here are some of my ideas, feel free to add anything you can think of that might help. Even if it means replacing some parts or something. I may be on a budget, but I might be able to hack it. We'll see.

Ideas:

1. Use higher octane gas.

2. Fixed the metal tube that goes from the top of the exhaust manifold to the bottom of the intake.

3. Gave it a full tune up a little while back. This would include air filter, fuel filter, spark plugs, plug wires, o2 sensor, distributor cap and rotor.

4. Maybe replace some of the other sensors that are there? Don't know which ones would affect this problem, though.
« Last Edit: September 29, 2009, 05:16:09 pm by Skunksmash »

Offline Skunksmash

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Re: Engine acts like it needs a set of glow plugs.
« Reply #1 on: September 30, 2009, 03:40:43 pm »
I can rule out the engine coolant temp sensor, as I have replaced that recently. Think it could be the IAC, aka an IAT vavle? It's this:

http://www.autozone.com/autozone/catalog/parts/partsShelf.jsp?displayName=Idle+Air+Control+Valve&currentPage=1&categoryDisplayName=Engine+Management&navValue=15900207&itemId=207-0&parentId=59-0

I have heard that it can cause the truck to run rough when it's cold. Is this true?

Offline VileZambonie

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Re: Engine acts like it needs a set of glow plugs.
« Reply #2 on: September 30, 2009, 07:26:30 pm »
Check the map sensor and vacuum hose.
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Offline Skunksmash

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Re: Engine acts like it needs a set of glow plugs.
« Reply #3 on: September 30, 2009, 09:56:04 pm »
Ok i will do that. But to clarify, you mean check to see if the sensor is like gummed up on the inside, correct? And if the hose is dry rotted? Also, can anyone provide a link to somewhere that tells you where the IAC valve is, as well as the map sensor? I looked around, but they all want you to buy your way into getting the info.

Offline VileZambonie

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Re: Engine acts like it needs a set of glow plugs.
« Reply #4 on: October 01, 2009, 12:04:18 pm »




That's the map sensor. you can't miss it.

Make sure you have a good vacuum signal to it 1st.
,                           ___ 
                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline Jay2D2

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Re: Engine acts like it needs a set of glow plugs.
« Reply #5 on: October 01, 2009, 12:44:36 pm »
Your IAC( Idle Air Control) valve Should be right on the side of your TBI unit. However the IAC is not the same as the IAT( Intake Air Temperature) sensor as you mentioned earlier... Just so you dont get confused in all of this.

Offline Skunksmash

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Re: Engine acts like it needs a set of glow plugs.
« Reply #6 on: October 01, 2009, 08:01:40 pm »
Ok thanks all I will check those out. There are a few things screwed in around the throttle body, though. I guess I can just check em all till I find which one is the IACv. A few people have me they like clog over time.

Offline Captkaos

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Re: Engine acts like it needs a set of glow plugs.
« Reply #7 on: October 02, 2009, 01:21:08 pm »
The IAC is located on the passenger side rear of the TBI.

Offline Skunksmash

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Re: Engine acts like it needs a set of glow plugs.
« Reply #8 on: October 03, 2009, 02:12:18 pm »
All right. While I'm at it, it looks like Autozone also sells a knock sensor, as well as a Throttle Position Sensor for the vehicle. Think there would be any point in replacing those, at this time? Might possibly help out with the problem? They sell 'em pretty cheap there.