'03 'Kon 5.3L dilemma!!!

[willbill15]

well, i have just under 150K miles on my 2003 yukon. I put a lot of aftermarket products on the truck right around 126K including 6inch lift, 35's, Black Bear, Hid's, rear tire carrier by TAG (everything about the carrier has been hell), new cv driver side, sound system with diamond audio amp and sub and probably some other....so the dilemma is the 5.3 recently has been running awful-idle is up and down and every where in between, and there's a major misfire that occurs under power. Finally the engine light was triggered, so i took it into my shop. Said there's two sensor (the O2 and something else) that need to be replaced as well as the valves are "hanging up." said it'd be around 2500-3000 to have them fix it (still waiting for an updated quote).

Anyways, what do I do?! sell as is and take the estimated $6500 in aftermarket as a loss? Part it out? buy a lesser mileage 'kon or even sierra and swap parts over? bite the bullet and fix the truck and hope to God the tranny lasts for the remainder of its life? or just swap to a newer 5.3 or 6.0?

Links to engine swaps/where to buy engines is helpful!!

I'm decently smart and intuitive with mechanical parts, but never have rebuilt an engine. I Have a lot of buddies that could help in the process tho, and i have a different vehicle that i could drive in the mean time. So, It just comes down of is it worth putting more time and money into this truck that I'm not 100% satisfied with to begin with?!

any comments help.

Thanks,
Will

 

[Huck]

Take it to another shop. No way on earth an O2 Sensor should cost that much, it's a $30 part. You can get a rebuilt engine for that price and a crate engine for a little more.

 

[willbill15]

yeah, they're saying with the misfire and the valve issues that they would need to rebuild the engine. I'm still waiting on the final diagnosis and quote tho....

 

[Jewel or Jalopy]

Valves are hanging up? Huh? Not sure how that would happen.

Take it to another shop. Get the real codes, if its just one or two cylinders misgiring it might be bad coils or wires.

A smoke test to look for vacuum leaks might help and you should try cleaning the MAF.

Also, o2 sensor codes are usually a symptom of bigger issues upstream which trigger an O2 fault when things get bad.

Good luck!

Sent from my Kindle Fire using Tapatalk 2

 

[dcwhybrew]

Get the exact details (write them down) and post up exactly what you were told. This doesn't sound right. A valve job on a pre 2005 land rover (which are $$$to fix) doesn't cost >$2k. You also need a second opinion.

For sake of argument, lets assume what you've stated is true and correct. If you sell it you're going to lose a whole lot more than the value of the aftermarket parts (which you almost always lose on whenever you sell a car with mods). Since there is a "major" mechanical issue your car will be significantly devalued in stock condition. So your "loss" is >$6,500. Therefore (again, assuming what you've stated is true) fixing or replacing the engine with a quality remanufactured engine is best. Besides, you may have the option of dropping in a 6.0L.

Again, call the shop back, have them write down the exact diagnosis and quote for repairs. Post it here for questions, thoughts, advice. Do some additional research on the Internet. Take the info you learned from here, and elsewhere and go to another reputable shop for a second opinion. This just sounds odd.

 

[willbill15]

okay thanks for the advice, Finally was able to get a hold of my shop today. Its been tricky cuz i've been out of town on vacation and they know it, so thats one of the reasons they were taking their sweet time to get to it. The shop said it is no longer mis-firing and he drove it about 25 miles or so to make sure it wasn't. he recommends not doing anything about the engine for the time being. However, my O2 sensor and MAF sensor are bad. They want 850 something to fix them....Can't i do it myself a whole lot cheaper?! Is the O2 sensor easy to replace? I know the MAF is simple because i just did it last year

That brings me to my next question...I have a MAC air intake and every couple months and having to clean it because of the excess amount of dirt that im finding in the intake hoses/tubes....I have not been happy with it at all, wondering if thats normal or if i should replace it with a good K & N? Or should I not spend the money if I might have the mis-firing come back to haunt me?

 

[dcwhybrew]

I would get home and get the truck away from that shop ASAP. They went from a $2500-3000 valve job to O2 sensors and MAF? Their later diagnosis is probably correct, but thats a big variation in diagnoses. Also, it is pretty odd that you would need another MAF within a year of replacing it. You need to verify that too. If it is true, find out what's causing it.

 

[Stein2088]

Just to add my .02 cents I had an 02 camaro and i cleaned my K&N filter I was having 02 sensor issues for about a year that I could find out what the issue was... Finally bit the bullet and found out that I had to much oil on the filter that over time passed on to the MAF sensor and gave it a false reading... As a result the car said I had a bad 02 Sensor... Cleaned the MAF and never had the problem again... (sorry if someone already said this leaving for class and didnt get to read the full thread)

 

[Hooch]

Yup i would be heading to a different shop asap

 

[Matt06Yukon]

Get that ****** cai out of there, no small performance gain is worth dirt getting into the engine. While you have it all apart clean the MAF too. After that, run the engine for about 20 minutes or so and then change the O2 sensors. Treat it to some fresh synthetic and see how she runs then. Ya gotta treat her right.