1995 Chevy S-10 Blazer 4.3L Fouling spark plugs

Tiny
RIVERJAMIE
  • MEMBER
  • 1995 CHEVROLET BLAZER
1995 S10 Blazer 4.3L 107K. The Autolite APP25 spark Plugs are fouling out within 5K miles. When I removed the plugs they were all very black, but not wet like oil. So after reading some of the posts it seems that the fuel filter and pressure regualtor should be replaced. I just installed new Distributor Cap and Rotor, Spark plug wires(all were original), and another set of Autolite APP25 plugs. My question is this. Has anyone replaced the pressure regualtor on this car for the same problem? If so did it solve it? How difficult is it to replace the regulator, any tips (gaskets, seals, adj.)? Should I also clean the injectors at the same time? If so any suggestions, I've never cleaned any before? Thank in advance.
Saturday, September 15th, 2007 AT 5:22 PM

4 Replies

Tiny
RASMATAZ
  • MECHANIC
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From: riverjamie
To: rasmataz
Posted: Sun Sep 16, 2007 5:12 pm
Subject: Hello Rasmataz
If you don't mind could you please review my post "1995 Chevy Blazer 4.3L Fouling spark plugs" posted on 9/15/07. I read some of replies to others. The plugs were in only for 1000 miles. After reviewing some other posts it seems that maybe the fuel pressure regulator might be bad? I found one from Dorman 55162 for the 4.3L engine. Have you ever installed one of these? Also I'm figuring that if the plugs were so fouled (pretty black) that the injectors must also be looking pretty bad. Any thoughts on replacement of fuel pressure regulator and cleaning the injectors? What's the best way to clean the injectors? Thank you in advance. Colin

Do you see VORTEC on top center of engine.
4.3L w/CPI spider man set up or it has TBI

Mam, You have to remove the upper plenum-if its the regulator the passenger side would be washed-up. The regulator comes with a kit-you have to drilled out the old one. Don't let nobody tell you -that you have to get the whole CPI unit its only about 40 bucks or so.

It doesn't have an individual injectors-its all confine in 1 unit with plastic tubings.
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Sunday, September 16th, 2007 AT 8:33 PM
Tiny
RASMATAZ
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Inbox :: Message
From: riverjamie
To: rasmataz
Posted: Sun Sep 16, 2007 7:20 pm
Subject: reply
Thanks for getting back so fast. Yes it says Vortex on the top of the engine. Do you think the FPR is the cause of the fouling of all the plugs? Have you used the Dorman Brand FPR for this problem and did it work correctly? What about trying to clean the injectors? So I bother? Thanks

If its gone it will-never use that brand-below shows how it looks inside


https://www.2carpros.com/forum/automotive_pictures/12900_vortec_1.jpg



Hope this helps
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Sunday, September 16th, 2007 AT 10:36 PM
Tiny
RIVERJAMIE
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Rasamtaz, I could not make out the small print on the photo. Are you saying that if the FPR is leaking it will look like the photo? Also if the injectors are leaking can I just replace an "o" ring or seal for them? I did pull out the MTV under the "Vortex" log and I belive that my passenger side may be clean like the photo? The dirver side looks like it may be a little wet or oily? Not sure have to pull upper plenum.
Thank you
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Friday, September 21st, 2007 AT 9:44 PM
Tiny
RASMATAZ
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Yup it will look like the photo, you can see the injector on the driver side. When you pull the upper plenum you'll see what am talking about-pax or driver don't matter.

To prove that's something wrong with it-when you open it up turn the key On to check for leakage.
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Friday, September 21st, 2007 AT 9:51 PM

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