1988 Chevy pick-up running bad.HELP

First off...how was it running before you got it tuned up? Was it tuned up as part of scheduled maintenance or was this the reason you took it to him to begin with?

Are you sure it's carbureted? An '88 should be TBI (throttle body injection) which does sorta look like a carb.

Concerning the wet plug...I suppose the area in the cylinder/head will be tight enough to keep any gas liquid in there. I wouldn't think a somewhat sealed off area would allow it to quickly evaporate, probably leftover from when you last ran the truck.

If it is TBI as I suspect, it should have an O2 sensor. Maybe someone can correct me if I'm wrong, but as I understand it, the ECM (computer) will run the engine rich until the exhaust gases get hot enough for the O2 sensor to work. Then the ECM will adjust the fuel/air mix based on what the O2 sensor is telling it. If the O2 sensor is bad or disconnected, it's possible that the ECM thinks the engine is still cold and therefore keeping it rich--in other words, as far as the computer is concerned your engine isn't warmed up yet.

This is just a possibility...based on the year your truck was produced. It should be TBI unless someone swapped the fuel injection setup for a carb setup. And TBI isn't tuned with adjustment screws and/or rods and jets like a carb is.

Does it smoke a lot when idling or driving?

~jp

First off...how was it running before you got it tuned up? Was it tuned up as part of scheduled maintenance or was this the reason you took it to him to begin with?

Are you sure it's carbureted? An '88 should be TBI (throttle body injection) which does sorta look like a carb.

Concerning the wet plug...I suppose the area in the cylinder/head will be tight enough to keep any gas liquid in there. I wouldn't think a somewhat sealed off area would allow it to quickly evaporate, probably leftover from when you last ran the truck.

If it is TBI as I suspect, it should have an O2 sensor. Maybe someone can correct me if I'm wrong, but as I understand it, the ECM (computer) will run the engine rich until the exhaust gases get hot enough for the O2 sensor to work. Then the ECM will adjust the fuel/air mix based on what the O2 sensor is telling it. If the O2 sensor is bad or disconnected, it's possible that the ECM thinks the engine is still cold and therefore keeping it rich--in other words, as far as the computer is concerned your engine isn't warmed up yet.

This is just a possibility...based on the year your truck was produced. It should be TBI unless someone swapped the fuel injection setup for a carb setup. And TBI isn't tuned with adjustment screws and/or rods and jets like a carb is.

Does it smoke a lot when idling or driving?

~jp

Well, I posted a reply from home, but for whatever reason, it's not working...

Was the truck doing this before you had it tuned up? Was the tune up scheduled maintenance or were you trying to correct a problem?

If it's an '88, it should have TBI (throttle body injection) instead of a carb, although at first glance (and to the inexperienced eye) the TBI unit looks a lot like a carb.

If it's TBI, it should have an O2 sensor. When the engine is cold, the ECM (computer) runs the engine rich until the O2 sensor heats up to operating temperature so that the oxygen content of the exhaust can be properly measured. If it's disconnected, damaged, or just plain bad, it could be causing the ECM to believe that the engine isn't fully warmed up, and therefore keep the mixture too rich. Could be the ECM itself...

Hopefully someone with more experience can chime in to answer this more in depth than I.

Does it smoke a lot when you start it? How about when you drive it?

~jp

Greetings,

Yes, it may very well be something small - time to replace your mechanic.

I owned an '88 C1500 so I am speaking for the type of truck that I owned. I cannot vouch for what may have been the older style still produced in that year, or a truck with any other motor configuration that what I owned (5.7L V-8 TBI). However, the 1988 vintage trucks that I am familiar with didn't use carburators, they used throttle body fuel injection (TBI) and electronic timing. There is nothing to "tune up/adjust" in a throttle body short of cleaning and/or replacing the components, and you couldn't adjust the timing on my truck because it was controlled by the ECM.

Your motor may be different (I believe that there were some carb models offered in a few pick-ups), but it sounds like your are running rich based on your description of the plugs. If you do indeed have a carb, then I'd take it to someone else with experience and let them check the mixture and jeting, as well as the automatic choke and a few other things, and get it dialed in a little better.

Good luck - Jonathan

Jon: Remember that the old 87 and older bodies stayed until 1990/1991 under the R/V instead of C/K chassis codes. I can be wrong, But i believe 88 R/V 3500's, Cab & Chassis, as well as 454 Suburbans could be had with a Carb.

I do know that TBI was available in 1986 and 1987 on the old body trucks with 305's & 350's. Yet the 4.3 V6 in 86 came only with a carb.

So it can get a bit confusing for a few years what parts a truck might have. Charles

Hello, I got the tune up because it was running rough.Sadly I'm not sure if it is a carb or a TBI, I'm a carpenter,LOL.the engine does give off a little white smoke when first started but stops shortly after.I had a Nissan pick-up a few years back and the O2 sensor went bad on it, and it ran real bad in 1st and 2nd gears till i got up to speed.My truck now runs ok in 1st and gets rough as i get into 2nd and 3rd gears ???Thank You every1 who has posted. TheHawk

Is it worse when engine is warm vs cold?

Its worse when its cold.

Is it a V8 or V6? Full size (1500, 2500, etc...) or S-10?

~jp

Actually... After reading your post I re-read the original post... I didn't see anything specific to indicate whether his truck was a full size or S-series... So I suppose we don't even know which engine we're dealing with here.

Maybe more info would be helpful from Mr. Hawk.

Either way, good info Charles. I'll file it away in the memory banks.

~jp

Does it matter what truck the engine is in if the symtoms are the same in a

1500 or a 2500 the fix should be the same,right.The title od my truck says 88 chevy and thats it,i have no markings on the truck its self.Well sorry for posting on a subject I know nothing about,but thats kinda what these forums are for.Ive been getting people telling me its my timing, anyone else think this could be it???? Thanks Every1, TheHawk

It's just that this information could eliminate a lot of guess work. Troubleshooting the symptoms you describe on a fuel injected engine would be much different than on a carbureted engine.

And an '88 S-series wouldn't have come with a V8, it would've been a V6. So we're not even sure which engine you have, and therefore can only give slightly vague advice.

Do this...Pop the hood, and find the distributor. Count how many wires are coming off the top of it and let us know.

~jp

stuck choke, stuck flote sort of thing. its getting to much gas

That's kinda a snide remark for a guy who had someone else who also doesn't know what they are doing tune up their truck. I'd tell you stop having the guy who services your air nailers (If you have them) work on your truck.

Ugh, just post the VIN# of the truck and one of us will reply back with what you have.

Ok lets pretend this is alt.carpentry.hawk Hawk I need a blade for my saw, what one should I get?

Now you guess is it a reciprocating saw, a circular saw, a bandsaw, a table saw, a jig saw. I bet you can write 3 pages for us just on one type of saw blade.

We could all guess if you like and later after you spend hundreds on parts your truck might run right. Better just post the VIN# to be sure.

;)

This still won't tell anyone if it's carb or TBI jp. Hint: post the VIN# or count the plug wires and take the top of the air cleaner off and tell us is you see wires right on top.

This is a TBI V8

up of TBI

I know it won't...but it be would SOME information as opposed to the NO information we have now other than it was made in '88 and it's a truck.

I also suggested counting plug wires.

And as was mentioned earlier in the thead, different engine were available with different models even within the full sized range of trucks. Hence my question regarding it's towing weight (1500, 2500,

3500).

~jp