Getting ODBII codes P0172 and P0175

I am getting ODBII codes P0172 and P0175 on my 97 Tahoe. It has the 5.7 Vortech. The truck runs fine and SES light comes on after driving for a while. Light is not normally on when cold. Has anyone has these error codes and if so, what the fix? Truck has about 117,000 miles on it.

P0172 System too Rich (Bank 1)
P0175 System too Rich (Bank 2)

Thanks,
Tony

It could be a faulty fuel pressure regulator or a dirty air filter, or distributor cap- rotor- wires-plug problem. If a fuel pressure test indicates 60-66 psi with the key on- engine off and doesn't drop after the pump quits I wouldn't think it would be a regulator problem

Jeremy-WI ,
Thanks for the info. I did a full tune up, including all items you listed, about 3000 miles ago. So I hope it isn't one of those components. I checked the fuel pressure and it's 58-59lbs. It didn't leak down. Do you think that's okay? I also changed the left and right O2 sensors located before the cats. I am still getting the codes though. It seems to throw the code when I'm hard on and off the accelarator. That would explain the codes being rich on both banks, but I wonder why the system can't compensate.


Everyone's comments are appreciated,

Tony

Fuel pressure is a little low, but I wouldn't replace it. If you have a scan tool, check what the cam retard is(or camshaft offset). You will have to rev the motor over 1000rpm for the value to be accurate and it should be +2 degrees to -2 degrees on a V8

I also get the P0175 code whenever I have to brake suddenly. I just clear the code and move. I do this because I have posted to this board and have been told to change some components and then seen replies that others have changed those items only to have the code return. I can't seem to pin down the cause or be able to duplicate it 100% of the time. I have a 96 Tahoe with the 5.7 and 123,000. If you find the cure please let me know. Thanks.

I had the same codes (p0175, p0172) on my 97 5.7 yukon and it turned out to be my fuel injectors. There is a recall on these injectors that applies to california trucks only. Dealer told me that they installed the new type injectors forgot what they were called, but no more codes and truck runs great! hope this helps!

I had the same codes (p0175, p0172) on my 97 5.7 yukon and it turned out to be my fuel injectors. There is a recall on these injectors that applies to california trucks only. Dealer told me that they installed the new type injectors forgot what they were called, but no more codes and truck runs great! hope this helps!


I have the exact same two codes (and only those 2 codes have ever shown up; always simultaneously) on my 1997 C1500 Pickup ext. cab 5.0L Vortec V8. I just figured the truck was out of tune (I dyno'ed on our inspection station in a training mode and the HC was running pretty high so obviously rotor/cap/plugs/wires need replacing). I was hoping that when I do this that the codes will disappear. Now I see that some of you have done that and codes still remian :(
Also, I was wondering if there is a place where you can check recalls and such things online...? You said you found a recall on the injectors and I was thinking maybe there is an online database that posts recalls so I can check to see if there are any on my truck.
Thanks!

I was getting P0175 on my '97 K1500 intermittantly but had no obvious symptoms of a problem.

I checked fuel pressure and it was within spec and held fine. I took a random guess that I could have sticking fuel injector(s) so I cleaned them and the code hasn't returned after almost 5,000 miles. Truck had 103K on it at the time.

I was getting P0175 on my '97 K1500 intermittantly but had no obvious symptoms of a problem.

I checked fuel pressure and it was within spec and held fine. I took a random guess that I could have sticking fuel injector(s) so I cleaned them and the code hasn't returned after almost 5,000 miles. Truck had 103K on it at the time.


How would I go about cleaning the fuel injectors...(i.e. what type of cleaner to use/what to avoid, etc.) thanks

How would I go about cleaning the fuel injectors...(i.e. what type of cleaner to use/what to avoid, etc.) thanks

Well...you could take it somewhere and have it done. I've seen ads for fuel injector service ranging from $50 to $99. Both are a rip-off considering there is almost no labor involved and the can of solvent is about $8.

I went the expensive route and bought a cleaning kit that runs on compressed air (there are kits available that work without a compressor too). The kit was $370 including various fittings and 12 cans of cleaner. I decided a long time ago that I'd rather spend more and do it myself than pay someone else of unknown competence. In the long run it will pay for itself anyway.

Not much I can think of to avoid. All you do is disconnect the fuel pump and set the pressure on the cleaner slightly below base fuel pressure to keep the solvent from being pumped into the gas tank. My theory was that after 103K miles the injectors could probably use cleaning, so what the heck. I followed this up by removing the throttle body and cleaning it, but the code disappeared after the injector cleaning.

I got the kit from the place linked below, but it appears that the price has gone up since I got mine.

http://www.thetoolwarehouse.net/shop/OTC-7659.html

The new fuel injectors are considered a MFI system, I put them in my truck a year or so ago(was less than $300 bought online and included all 8 injectors, fuel pressure regulator and a gasket)