95 s10 4x4 blazer rough run and stinks 135k

I am working on my s10 and cannot read with a code reader. I get link errors. so.... I have changed the plugs, wires, rot/cap, and have been told crank sensors go bad on these guys. I also changed EGR cuase it was
heavily caked and sticking/worn out.
Any ideas are welcome. I hate to throw random money at it wildly but I wanna fix it myself if I can.
She's running rough, has excessive exhaust stink like carbon stink.
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Is this a W-code motor? L35 in the glove box or W in the 8th VIN position. If so, you could have a leaking regulator/injector. Replaceable as a unit, I pid under $400 for the injector and "nut kit" (actually fuel lines from the back of the manifold to the injector inside the manifold). If you have a fuel pressure gauge, hook it up and see if it holds pressure overnight.

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Reading a manuual, I see the pressure should be 58-64. Well, I get 56 and about 64 when it spikes, but as I said before it doesnt hold once the engine shuts off.
Mike Levy wrote:

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Sounds like the regulator or nut kit unless a failed check valve in the gas tank will cause this. I replaced my injector and nut kit myself. Took the better part of a day but those lines are tough to line back up at the back of the plenum, there are slots that a plate slips over to hold them in place. If you're opening the plenum, may as well spend the extra $40 to replace the nut kit.
Sounds like you're relatively mechanically inclined, you'll be doing this yourself? Before I did mine the most I'd done was replace spark plugs and fuel filter. I have a Haynes manual and it describes the procedure pretty well. I would suggest replacing the cap and rotor while you have the plenum off, it's MUCH easier to get to, but I see you've done that already.
If you finally decide to replace these parts and do the work yourself, I got mine from www.partszoneonline.com , I had the parts relatively quick, it's a GM dealer so they're new GM parts. I also saved almost $210 compared to list price. The injector is part number 17113673 and the nut kit is 17112705. This is actually a common failure on these engines. How long has yours lasted? Mine's a 94 and had 101,000 on it when I replaced the injector parts this time last summer. I'm now at 111,200 with no injector problems yet.
As a last check, pull off the black/orange "Vortec" cover, pull out the IMTV (Intake Manifold Tuning Valve) that's under it and peer inside with a flashlight. You'll see the inside of the intake, I think the injector is right there, but you'll be able to take a look and see if the inside looks REALLY clean, or if there are puddles in there at all, though you won't see much of the surface area inside, you'll likely be able to see enough...

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oh yeah. I've had that Vortec thing off once recently. Its all built up in there with sludge. This was back when I had to change the EGR valve. The brakes practically caused an accident from lack of pressure due to that valve failing in one position.
I just got back from the local auto parts. They ordered me what I need fuel wise. I still have the crank sensor I want to put on and I think I know where it is after seeing anotther manual at the store.
How does your pressure behave? Dos the pressure stay up when the engine is shut off? This one goes right to zero and when I gun the engine a little it drops down to like 52 or 54 before going back to 56.
Mike Levy wrote:

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I just checked whre the sensor shouldbe according to the diagrams and guess what? There's a place for it but there never was one there. Maybe this thing has a bit of 1994 technology in it. It was one of the first 95's to come out.
ed wrote:

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I hear ya on the EGR, had it clog up on the highway, re-engaged cruise after having to slow for someone in my lane with noplace to move to, going uphill, SES light blinks on. Got to my off-ramp and it was idling REALLY rough with no vacuum assist. GM fixed mine free under an extended service campaign, got a re-programmed PROM and new EGR out of the deal. I don't know how the fuel pressure behaves, I based my diagnosis solely on the symptoms of how the truck started and ran. It was hard to start 45 mins to 4 hours after running, because the engine was basically flooded, and running a little rough at idle. Mine hadn't gotten to the point of actually "cleaning" the manifold yet. Both symptoms cleared up right after replacing the injector. I never did and still haven't hooked up a fuel pressure gauge.
BTW, your truck is 1/2 OBD-1 and 1/2 OBD-II, 95 was a change-over year for the OBD system, it may not have all the sensors OBD-II computers need, but has more than OBD-1 computers need, and has a more sophisticated system. I bet you can't read codes out of the computer using the paperclip trick...

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I'd vote in Mike's camp on the CPI injector being the problem. Generally if you take the intake manifold tuning valve out (it's the round thing in the middle top of the manifold and the only thing with wires going to it) look down inside the manifold and if one side is wet then the pressure regulator is leaking. Also the 'plastic' lines or so-nut kit lines can crack and leak fuel. Look at www.lindertech.com for a discussion on the CPI unit and some checks you can do. They also sell rebuilt units. Also www.s-series.org is a group of s10 owners but the site is presently down. In the section on 4.3 engines there's been a discussion on CPI replacement and problems. You can get part number via www.acdelco.com Places to buy include www.gmpartsdirect.com and www.rockauto.com. There may be other online sources. Worst part of the job was getting the retainer plate off the back of the manifold that holds the nut kit in place. You'll need a #30 torx head and 1/4" drive socket. Not much clearance between manifold and firewall. I change mine about 1 1/2 yrs. ago because of black smoke at startup, rough idle and sulphur smell. Truck now runs like new with 90k miles.
HTH

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The s-series.org site is great. I'm a member there. The forums are actually up, but the main site is under re-construction. Forums are http://forums.s-series.org I got my parts from www.partszoneonline.com as I mentioned in another post. I went with new parts because I was more comfortable going that route. My Haynes manual says the unit is not serviceable, so I didn't want to risk it.
On Sun, 20 Jul 2003 01:10:34 GMT, "DonW"

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I went to that board you mentioned Mike. OMG!! I am rejuvenated!! I jusst wanna go out and tear off that intake manifold right now and not take any prisoners!!
I have some parts to take back (unopened) and some to pick up today and I may jsut first check to see if I just dont have an injector stuck open.
Mike Levy wrote:

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ok...I'm into it. Its the center mounted regulator and feed which splits 6 ways to each cylinder. I havea pool of fuel in the plenum.
ed wrote:

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Found entire kit at a local parts place (Borg Warner replacement) Talk about $$$$. Whew but...this is the fix. I can see how it would draw air/fuel instead of just air in the plenum when the regulator is leaking into the plenum.
Putting kit on now on a nice day. Long live the mechanic!! Thanks to you guys!!
keith wrote:

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Dude, thats right where I am. sulphur smell, black junk all around the exhaust pipe. runs pretty good but rough and misses once in a while.
Looks like I'm changing that bad boy... better get ready for an all day affair. thanks for the links.
DonW wrote:

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Well, I found another regulator/injector assembly for $100 less and looked exactly like the Borg Warner one, same materials etc. so I went with that. Still 300 bucks though.(aftetr adding a gasket to the list)
It ran a little crappy at first but ran it a while and it has come around to being 99.9% rock solid. ed wrote:

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