Blazer Problem... (Update)

[Paulson]

I don't really know how to explain it, but I'll try my best and see how it goes.

This problem has happened on and off since last summer but now during winter it's been really bad.

Basically, when I go to start the thing, it starts up just fine, and within 2 seconds the rpm's go from 1 or 1&1/2 down to half and the engine is struggling to idle and finally stalls. It will always start, but it will stall.

It will continue to run if I get it in gear fast enough. However, as I'm driving, sometimes I lose power (I can watch the rpm gage temporarily drop) and occationally when I'm on the highway all the sudden the vehicle will jerk really bad (acts as if the engine stopped for a moment) but just keeps on going down the highway.

So far I've changed the fuel filter on it, but still no go.

The service engine light will come on when it jerks or stalls, but will go off after a few successful starts (which doesn't happen as of late because it's really bad at the moment)

Does anyone have any ideas as to what could be the problem or what would be an appropriate thing to go about fixing?

(It's the original motor/tranny w/159,680 miles)

Thanks in advance

 

[Pepsi90919]

perhaps a throttle position sensor. but since there is a code being thrown, have it scanned.

end of thread.

 

[Paulson]

I had it scanned a while back when it was doing it, and it came back as an unrecognized code

 

[iversonyin]

the problem is call "american cars"

i know, i'm an import fanboy

 

[Paulson]

Well thanks for the wonderful insight... because of your post iversonyin, I'm sure my Blazer will run 100% from now on.

 

[iversonyin]

Originally posted by: Paulson
Well thanks for the wonderful insight... because of your post iversonyin, I'm sure my Blazer will run 100% from now on.

your welcome,

why not go to mechanic and check it out. its 158,000 miles...when the last time you have a check up?

it possible that your engine is dieing....

 

[Paulson]

Well I thought I'd get some opinions before taking it there... It had some tranny service work done over the summer and it had been running great for a long time. Once I get the thing running it runs perfect, I mean when it is working right the engine idles perfectly.

The sparkplugs have just been changed, a/c compressor was changed a while ago...

 

[wischeez]

No codes thrown?? Could possibly be a bad EGR valve. (pintle sticking because of carbon deposits)

 

[iamwiz82]

Have you cleaned/replaced your IAC? You can go junkyarding for parts for cheap since the 4.3L is plentiful.

 

[CrackRabbit]

Cam position sensor possibly? Not completly dead but dead enough to cause it not to ilde properly.
TPS is another possibilty like Pepsi said.
Maybe Transmission sensors.

 

[Paulson]

Well I'll take it to a seasoned mechanic since it doesn't seem like something simple enough to do on my own...

Eh, used vehicles are all about replacing parts but they're still cheaper than buy new ones

 

[MikeMike]

just a possiblility, but i had some weird issues with my 98 jimmy, that were caused by a faulty wireing harness in the steering column.

MIKE

 

[TechnoKid]

IAC or fast idle valve, but that wouldn't really explain the sudden loss of power when cruising; I'm sure the two are related. Is your throttle at the same posistion when the power loss occurs or does it happen say when you press the gas a little more or let off of it?

 

[SWScorch]

same problem on my mom's 95 Blazer, it was a faulty Throttle Position Sensor as Pepsi31415926535 suggested.

 

[Toastedlightly]

Could be a spark problem, an air problem, fuel problem... wiat... I dunno?

 

[Paulson]

Well I helped my dad change out the throttle position sensor but I don't know if it worked right or not, because the problem with the blazer was intermittent, not all the time, so who's to say what it could be...

However, upon taking off the one that was on my vehicle, we noticed that the little assembly that turns was incredibly loose, whereas on the new TPS, you couldn't even move it, so hopefully you were right and that's all that needs to be done...

Thanks for the help AT!

 

[radioouman]

Throttle position sensor went bad on my 93 Dakota... well, the original was on it when I bought, and so I installed a replacement. 6 months later the replacement went bad, so I put the original back in and haven't had any problems since.

 

[Paulson]

They seem like very little finicky devices...

I haven't driven this far or long enough to tell if it's going to work out alright or not (because the problem happened very randomly and sometimes wouldn't appear for up to a month... so who knows)

Magically the heat started working in my Blazer once again as well so who knows...

As long as it runs and does what I want it to do I'll definitely keep the damn thing!

 

[TitanDiddly]

Originally posted by: Paulson
They seem like very little finicky devices...

I haven't driven this far or long enough to tell if it's going to work out alright or not (because the problem happened very randomly and sometimes wouldn't appear for up to a month... so who knows)

Magically the heat started working in my Blazer once again as well so who knows...

As long as it runs and does what I want it to do I'll definitely keep the damn thing!

How is the milage?

 

[quizzelsnatch]

so... who else thought he was talking about problems with the Blazer team?

 

[Shawn]

So did replacing the TPS fix it then? I have similar problems with my car and I think my TPS is bad.

 

[Paulson]

Originally posted by: PhasmatisNox

Originally posted by: Paulson
They seem like very little finicky devices...

I haven't driven this far or long enough to tell if it's going to work out alright or not (because the problem happened very randomly and sometimes wouldn't appear for up to a month... so who knows)

Magically the heat started working in my Blazer once again as well so who knows...

As long as it runs and does what I want it to do I'll definitely keep the damn thing!

How is the milage?

Well I don't know, I have to fill up the tank and run it for a while out on the highway to get a good idea of where it stands...

I think the fan clutch needs to be replaced as well because I think the fan isn't operating correctly...

But at least it seems to be running a lot smoother when I took it out driving tonight...

 

[Pepsi90919]

Originally posted by: Paulson
Well I helped my dad change out the throttle position sensor but I don't know if it worked right or not, because the problem with the blazer was intermittent, not all the time, so who's to say what it could be...

However, upon taking off the one that was on my vehicle, we noticed that the little assembly that turns was incredibly loose, whereas on the new TPS, you couldn't even move it, so hopefully you were right and that's all that needs to be done...

Thanks for the help AT!

AT didn't help you, i did

 

[Paulson]

Well yes, you were a part of the convincing crowd... SWScorch also had a convincing post...

Surprisingly it was an easy swap once you get all the other crap out of the way...

 

[imported_hscorpio]

Originally posted by: wischeez
Could possibly be a bad EGR valve. (pintle sticking because of carbon deposits)

If it starts acting up again after the new TPS install you should check the egr next. I had nearly the same symptoms you described in my old s10 and it turned out to be the egr valve. I fixed mine just by cleaning it good overnight, but they are under $10 I think. Kind of a bitch to take off on the 4.3's though.