I am wondering if anyone has an opinion about my 98 Silverado 5.7 engine. On the way home 2 weeks ago pulling a 2700lb camper she started bucking when I would accelerate. While trying to accelerate it would flash the SES light. The code is p0300 so it isn't very helpful. I replaced the 3 year old plugs and the 5 year old plug wires and reset the computer, no change. I broke one of the tabs on the distributor so had to replace that, no change.
There are no "obvious" vacuum leaks, battery and starter are less than 1 year old, fuel pressure checked good earlier this spring. I know I am just throwing parts at it but that is all I can figure for now. It does have just over 200,000 miles so the possibilities are numerous. I have also read the cats may be bad so I think I can unplug the sensor to verify that.
Tim H said
Jul 10, 2013
I had the same type of issue on my 99 Suburban it turned out to be a dirty air filter and dirty fuel filter. It ran like a champ after I replaced those two items
Come to think of it one other time I also had a gear on the distributor go bad and replaced the crank position sensor. Both easy and made a difference.
-- Edited by Tim H on Wednesday 10th of July 2013 06:18:11 PM
jim larson said
Jul 10, 2013
timing chain?
SShink said
Jul 10, 2013
I recently had low idle issues with my '03 GMC, and it went away when I used the 3M MAF and throttle body cleaner kit. Something in the induction system maybe?
4-door Chevelle said
Jul 10, 2013
I know our original small blocks from a long time ago came with a plastic coating on the gears that let go with time causing them to be very loose. I am sure that was old technology and this 1998 vehicle does not have any plastic the the timing gears. It is still possible that it is old and stretched out I suppose.
I was also reading that the mass air flow (MAF) sensor needs to be cleaned somewhat regularly so I will try that as well as using a throttle body cleaner (which I have never done either).
4-door Chevelle said
Jul 11, 2013
I tried getting my fuel filter off this past spring, it isn't going anywhere and remaining in it's current form. (kind of like my brake lines) I think I may need to just tear in to it to replace the metal inline fuel filter and possibly some fuel lines. I will check the air filter just for grins.
I did also read about the distributor gear and the crank position sensor is on my radar as well.
I almost ALMOST wish I wasn't going Up north this weekend so I can work on it but since I am driving my Chevelle to Silver Bay I certainly can't pass that up!
Chris R said
Jul 12, 2013
Back in my auto tech days. Ive worked on many of those era trucks with that problem, even my 97 Tahoe had the same type of thing, accept mine was a missfire all the time. For the case of my Tahoe, I had to replace the spider assembly with a newer updated unit. I still need to get in and replace my distributor gear though but that wont cause a random missfire. From the customers vehicles I have worked on with this problem, they were all over the board from plugs and tune up parts that were never changed to low fuel pressure so I couldn't give you the exact specific problem your having.
Enganeer said
Jul 23, 2013
Darren,
If you pull the engine and swap it, I would be interested buying the old one as a core to play around with.
John
-- Edited by Enganeer on Tuesday 23rd of July 2013 03:38:57 PM
4-door Chevelle said
Jul 23, 2013
OK, so I finally took it to a shop. He worked on it a bit and found cylinders 2 and 8 with compression of only 55. I think this means I need to find another truck as I don't think I am up to tearing down an engine. It has 226,000 miles on it with original tranny. I love the truck but I don't think it makes sense to sink any more money in to it. I am seeing Chevy trucks on Craigslist like mine (but running) just under $2,000. So if I sell my Toyota and vacation time at work I can buy another truck. I should be able to sell mine as well? I am seeing broken stuff asking $1,000 so maybe there is still some value after all?!?
Enganeer said
Jul 23, 2013
Was it a worn rings, head gasket or worn out valves?
67ss said
Jul 23, 2013
Should be able to do a quick leak down check on it to find out. Suspect it is a valve related problem, I have not seem many ring problems with those engines.
4-door Chevelle said
Jul 23, 2013
Whether it is rings, head gasket or valves I am kind of not in teh mood to tear in to it. If it was the Chevelle then there would be no question as I know her.
bowtie said
Jul 23, 2013
That's the same long block I have in my Chevelle. The block is the same basic thing as the 330hp crate engine too. The heads are the Vortec ones...... anyway, if you wanted a GM replacement engine I can do one for about $2200. It would be a long block w/o manifold, you just swap over your stuff.
Chris R said
Jul 24, 2013
Darren, depending on what you plan to do with the truck. I could use a bunch of parts for my 97 Tahoe. Had to get it out of 2 year storage Sunday night because my current DD I drive has finally s&^t the bed and my replacement car I purchased last fall isnt ready yet. So im falling back on my 97 for now and could certainly use some parts. Stuff like the AC compressor, alternator, common wear items like tires, etc.
Lost in the 60s said
Jul 25, 2013
A $500 engine swap is the cheapest route, if you have the place and time.
I would hesitate to buy another truck with high miles. You could end up in the same place in a short time.
4-door Chevelle said
Aug 8, 2013
I wasn't in the mood for all that work so I got a fair price as a trade-in for a newer Silverado. Lots of great ideas here if I was up to the challenge. Must be getting old but please note... if it was the Chevelle I would have that engine out in a heart beat!
Lost in the 60s said
Aug 9, 2013
You'll enjoy having the LS engine for performance and fuel mileage. It was like night and day difference when I sold my '95 and bought the 2000.
I am wondering if anyone has an opinion about my 98 Silverado 5.7 engine. On the way home 2 weeks ago pulling a 2700lb camper she started bucking when I would accelerate. While trying to accelerate it would flash the SES light. The code is p0300 so it isn't very helpful. I replaced the 3 year old plugs and the 5 year old plug wires and reset the computer, no change. I broke one of the tabs on the distributor so had to replace that, no change.
There are no "obvious" vacuum leaks, battery and starter are less than 1 year old, fuel pressure checked good earlier this spring. I know I am just throwing parts at it but that is all I can figure for now. It does have just over 200,000 miles so the possibilities are numerous. I have also read the cats may be bad so I think I can unplug the sensor to verify that.
I had the same type of issue on my 99 Suburban it turned out to be a dirty air filter and dirty fuel filter. It ran like a champ after I replaced those two items
Come to think of it one other time I also had a gear on the distributor go bad and replaced the crank position sensor. Both easy and made a difference.
-- Edited by Tim H on Wednesday 10th of July 2013 06:18:11 PM
timing chain?
I recently had low idle issues with my '03 GMC, and it went away when I used the 3M MAF and throttle body cleaner kit. Something in the induction system maybe?
I was also reading that the mass air flow (MAF) sensor needs to be cleaned somewhat regularly so I will try that as well as using a throttle body cleaner (which I have never done either).
I did also read about the distributor gear and the crank position sensor is on my radar as well.
I almost ALMOST wish I wasn't going Up north this weekend so I can work on it but since I am driving my Chevelle to Silver Bay I certainly can't pass that up!
Back in my auto tech days. Ive worked on many of those era trucks with that problem, even my 97 Tahoe had the same type of thing, accept mine was a missfire all the time. For the case of my Tahoe, I had to replace the spider assembly with a newer updated unit. I still need to get in and replace my distributor gear though but that wont cause a random missfire. From the customers vehicles I have worked on with this problem, they were all over the board from plugs and tune up parts that were never changed to low fuel pressure so I couldn't give you the exact specific problem your having.
Darren,
If you pull the engine and swap it, I would be interested buying the old one as a core to play around with.
John
-- Edited by Enganeer on Tuesday 23rd of July 2013 03:38:57 PM
Should be able to do a quick leak down check on it to find out. Suspect it is a valve related problem, I have not seem many ring problems with those engines.
Darren, depending on what you plan to do with the truck. I could use a bunch of parts for my 97 Tahoe. Had to get it out of 2 year storage Sunday night because my current DD I drive has finally s&^t the bed and my replacement car I purchased last fall isnt ready yet. So im falling back on my 97 for now and could certainly use some parts. Stuff like the AC compressor, alternator, common wear items like tires, etc.
I would hesitate to buy another truck with high miles. You could end up in the same place in a short time.
You'll enjoy having the LS engine for performance and fuel mileage. It was like night and day difference when I sold my '95 and bought the 2000.