Author Topic: 87 Blazer  (Read 13266 times)

Offline jaden1997

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87 Blazer
« on: January 30, 2014, 03:16:12 pm »
My 87 S10 Blazer stalls when i drive and come to a stop. I've checked just about all the obvious things, but I'm now leaning toward something with the distributor. I was wondering if anyone knew about anything that could be causing it to stall out. Btw it starts right back up each time.


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Offline blazing816

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Re: 87 Blazer
« Reply #1 on: January 30, 2014, 03:40:33 pm »
you check the idle??....could be the idle set to low.
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Offline jaden1997

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Re: 87 Blazer
« Reply #2 on: January 30, 2014, 05:08:00 pm »
 I adjusted the idle screw a few times, but there was no change in the truck stalling out.


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Offline bake74

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Re: 87 Blazer
« Reply #3 on: January 30, 2014, 10:26:21 pm »
My 87 S10 Blazer stalls when i drive and come to a stop. I've checked just about all the obvious things, but I'm now leaning toward something with the distributor. I was wondering if anyone knew about anything that could be causing it to stall out. Btw it starts right back up each time.
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     Automatic trans or standard ?  Which engine do you have ?  Does it start to run rough as soon as you slow down or only when you come to a stop ?  If automatic, does it downshift ok through the gears as you are slowing down ?
#1: The easiest and most obvious solution to any problem is 99% of the time correct.
#2: There is no such thing as impossible, it just takes longer.
  74 k10, 77k10    Tom

Offline jaden1997

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Re: 87 Blazer
« Reply #4 on: January 30, 2014, 10:55:06 pm »
Automatic transmission, 2.8L V6, it runs rough when i slow down, like you can hear it trying to shut off. Then when i get to a stop it usually does shut off. Yeah it downshifts fine as i'm slowing down.

I don't think it's a transmission problem at all since it will idle oddly in park.


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Offline Irish_Alley

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Re: 87 Blazer
« Reply #5 on: January 30, 2014, 11:22:27 pm »
vacuum leak, the tbi base gasket can be sucked in and cause a problem then once you hit the brakes you will draw more vacuum and stall. this is one theory.

another thing is fuel pressure problems, the tbi uses in tank fuel pump the rubber hose between the pump and fuel pump assembly can crack and cause bad pressure or the pump can cause bad pressure or the sock can cause bad pressure. but fuel problems are usually if it runs crappy other times then just stopping.

egr can also cause a stalling problem.

does you cel light up when you first start the truck? does it stay on? any codes stored?

one more thing, does it stall if you take it out of gear and come to a stop or slow down? tcc in the trans
« Last Edit: January 30, 2014, 11:32:32 pm by Irish_Alley »
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Offline jaden1997

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Re: 87 Blazer
« Reply #6 on: January 31, 2014, 06:13:40 am »
I checked for vacuum leaks already and there weren't any. I just rebuilt the throttle body too. I don't think there's anything wrong with fuel because i did a test and i'm getting 13 psi of fuel, which is the right amount. I cleaned out the egr just to see what would happen before. The light isn't on. If i put the truck in neutral then slow down or stop, the truck still stalls out. But i didn't think it was anything in the transmission because the truck will idle weird even when it's in park.


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Offline Irish_Alley

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Re: 87 Blazer
« Reply #7 on: January 31, 2014, 11:07:10 pm »
what vacuum numbers are you pulling?
when its acting up does it still read 13 psi?
does it act up 100% of the time idle and coasting?
« Last Edit: January 31, 2014, 11:08:57 pm by Irish_Alley »
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When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline jaden1997

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Re: 87 Blazer
« Reply #8 on: February 01, 2014, 08:31:31 pm »
Yeah it reads 13 psi all the way until it shuts off. The. It goes to 0 of course. When I first start up the truck it idles fine. If I let it sit for about 10 minutes, it will start to idle bad.... Or if i start it up and drive for a few minutes then it will idle bad and most likely shut off.


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Offline jaden1997

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Re: 87 Blazer
« Reply #9 on: February 01, 2014, 08:32:36 pm »
Vacuum numbers?


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Offline Irish_Alley

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Re: 87 Blazer
« Reply #10 on: February 01, 2014, 11:13:21 pm »
yes numbers. idle vacuum and cruising vacuum. how easy does it start after the stall any smoke?
do you have to wait for it to cool down before the idle or stalling clears up?
« Last Edit: February 01, 2014, 11:48:27 pm by Irish_Alley »
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline Irish_Alley

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Re: 87 Blazer
« Reply #11 on: February 01, 2014, 11:59:00 pm »
egr test
http://www.gmsquarebody.com/forum/showthread.php?t=6902
the thing im thinking about is when its cold it runs fine but once it OT it starts to screw up. maybe the coolant temp sensor? unplug it and see how it runs (should make it rich) it has to be sensor related since its seams fine in open loop (cold)but once it closes it runs like crap. i wana say the o2 sensors on those engines are ignored till OT then the will start doing their job. i know im all over here but stay with me. also the iac kind of sticks out a little
« Last Edit: February 02, 2014, 06:44:02 am by Irish_Alley »
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline jaden1997

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Re: 87 Blazer
« Reply #12 on: February 02, 2014, 07:34:09 am »
Right I see where you're coming from. I'll have to get back on the vacuum numbers.

But it starts just fine after each stall. I don't have to wait or anything. I'm thinking that it's sensor related also. As far as the iac, i cleaned the one that was on there and even tried a different one, but there wasn't a change.

I'm not so sure about the egr valve. I took it off and cleaned it, but it wasn't getting stuck at all. I can certainly read about it in the website and see if there's anything I missed.

When I was looking around the engine once, I think I found 2 coolant temp sensors. I can take a picture of it if you need me to. I just unplug them and see if it runs differently?


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Offline VileZambonie

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Re: 87 Blazer
« Reply #13 on: February 02, 2014, 09:37:30 am »
I adjusted the idle screw a few times, but there was no change in the truck stalling out.


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The IAC valve controls the idle speed
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Offline Irish_Alley

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Re: 87 Blazer
« Reply #14 on: February 02, 2014, 10:09:06 pm »
One sensor cts tells the ecm the coolant temp its in the intake near the thermostat housing. The other is the coolant switch its in the head and goes to the dash gauge. My 94 was running like crap while taking off if you didn't floor it it would stumble and try to stall.  I got to thinking and unplugged the egr solenoid and she ran good. Plugged it back in and 10 feet down the road she started bucking unplugged it again and she cleared right up. Now our truck are acting different but unplug it and see what it does
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes