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Oh, and I’m going to replace both the valve cover grommet and the oil cap since it appears to be worn out if it’s popping off just by brushing up against it the wrong way.
sounds like the factory amp got shorted when you did the “oopsie”, killed the amp but caused it to draw power…probably by fusing the contacts on the internal switch circuitry.
Never been a big fan of stock amplifiers in cars….seems to just be one of those things car manufacturers have a hard time getting “right” when it comes to anyone owning one and being any level of an audiophile.
There is no chance of an exhaust leak as I’ve replaced both exhaust donuts with new ones and there is no traces of a “tick” from a typical exhaust noise.
Something I ran across the other day that just dawned on me is that one of the things that I was messing with when I was trying to fit the stock airbox on, was the oil filler tube. I needed to reposition it to the passenger side about 2 inches or so. I unbolted it, drilled a new hole on the frame that goes over the alternator and bolted it down. The reason I bring this up, is that while I was messing with the airhorn gasket, I somehow managed to unscrew the oil cap and dropped it on the ground. Apparently that was a big no no as my STFT’s both shot up to 25 on my Actron scanner….this was the second time while working on it that day that I had done that very thing.
Now, I don’t know if you believe in it or not, but I think that dumb cap coming off the second time may have been someone telling me something. For the fuel trims to go so haywire just from removing the oil filler cap, I’m thinking that if the gasket that the filler tube goes into the valve cover is leaking that my problem lies within that area.
It would make a lot of sense too. The van ran great before I worked on the E fan. While working on the E fan, I decided to get side tracked with the air cleaner assembly. In order for the air cleaner assembly to fit, the oil filler tube needed to be moved out of the way. That was seemingly an easy thing to do-drill a new hole and bolt it into the new position.
So, I’m going to find a way to test my theory…but this time I’m going to make a video of the process. I’ll either fail or I’ll succeed, but either way, I’ll post it here for everyone to see.
Oh, and to answer some questions raised….both 02 sensors are brand new as of spring 2011 ( Standard brand ) though one problem I had with the drivers side was that the bung hole when the custom exhaust was made wasn’t large enough for the end of the new O2 sensors. I ground it out with my dremel the best I could, tried to get a tap in there to open up what I couldn’t with the dremel ( very tight fit…couldn’t drop the exhaust enough for clearance…most of it was done blind ) and when I installed the drivers side O2, it was still pretty tight, I’m sure at the very least the end of the O2 sensor got a little dinged up. The plan was to find an actual 18mm tap and run it through the hole to clean it up completely since the one I had borrowed was just to clean up the threads, So I’ve always suspected that that sensor might not be at 100%. It got the van running and the readings never seemed out of range, so I’ve left it be.
freeze frame data from my Actron and Live Data
http://youtu.be/WHW4rzoyVGYSince I’ve never actually taken any classes on reading most of this info, I’m usually just taking a stab at what it means ( I just figured out the LTFT and STFT acronyms recently )
The problem is, I’m still coming up short putting all the pieces of the puzzle together as easily as someone with learned knowledge of such things. It’s helped me to become a better home mechanic, but I still have a lot to learn when it comes to computer diagnosis. It’s the relationship amongst the sensors that I still havne’t gotten a complete grasp of yet. What I need to do is probably do more baseline testing to know where the numbers “SHOULD” be so that I can recognize when they aren’t where they should be.
BTW, not to make a long thread longer, but it seems that anytime I have a problem with this van, it seems to become a protracted issue and not something that is just easily solved. Reassigning wires to the new computer went really well, except that the O2 sensors wouldn’t come online. It took me a couple of weeks to find that the sensors I had in the van weren’t compatible with the computer I was using…whodathunkit? Wired in the proper sensors ( of course, I couldn’t get them with the proper plug, that had to be redone too! )
Then the waterpump springs a leak at the gasket and after the 2nd failed gasket, I finally figured out how to put the water pump on without damaging it..hasn’t given me a problem since.
The original broken mechanical fan was a fun one to get off the water pump, but once I figured that out…piece of cake….only to have it break 8 months later and bring me to my current ordeal….Isn’t life grand?
I’ll eventually get this figured out, but in the meantime I’ll be scratching the remaining hairs on the top of my head out.
I’m dealing with the same codes with my Chevy van. I have a 1996 explorer with a V8 if you want any baseline readings from, I can give them to you. It runs like a champ and has been one of the least problematic vehicles I’ve owned. I’ll pull fuel pressure readings from it and let you know what I’m running at.
In the mean time, don’t waste your money on O2 sensors unless they are old and are due to be changed ( if they are slow to respond or sluggish ).
My problem is your problem though. My van is a 1998 Astro with a 1999 Savannah V8 in it ( vortec ) which runs a high PSI pump. The pressure drops too low and the motor won’t run because the poppet valved on the injection system won’t open. I don’t have that problem currently. However, my pump recently got a little noisier than when I got the van. Unfortunately, the replacement pump is not cheap at all ( like $3-400 not cheap ) so I’m not gunning to throw parts at my van to fix my P0171/4 codes either.
My van starts immediately, runs smooth, no idle problems to speak of and gets 16mpg. However, when the codes first showed up, I was getting 16mpg sometimes, and other times I was getting 14mpg. Before this, I was getting a solid 15.5mpg every tankful.
I changed the exhaust donuts, I’ve double checked my intake system. My problem started when I switched over to an electric cooling fan. The bigger issue I have is when you roll down a window, you get rich exhaust vapors inside the van…obviously not anything good.
One thing I am going to try is a couple of bottles of ISOHEET. Bad fuel or water in the fuel could be a problem potentially from my internet searches and I do have a decent amount of water coming out of my tailpipes. It’s cheap and can’t hurt anything, and if there is a bunch of water in my fuel tank, it could take a while for it to get cleared up on its own….my van sits every other week when I’m not driving it to work ( carpool ) I’m going to get gas at a different gas station this time and see if that helps anything too.
Keep us updated!
I believe the second set of values is after I reset the fuel trim with the scanner. If there is something in particular you want to see, I’ll get a picture of it ASAP.
Here’s what I did today. I listened as hard as I could for any vacuum leaks. I couldn’t find any that were audible. So, I retraced my steps to where I was before I started getting the codes-which was trying to get the stock air box to work with the van instead of the elbow and spectre cone filter set up that I bought the van with.
Found that the clamp for the connection between the MAF and the air horn wasn’t very tight, I could rotate the MAF by hand. The Airhorn to thottle body fit was a little loose also. When I was trying to fit the airbox on, I managed to force the airhorn off the throttle body. It’s held on by a screw down clamp on the rear of the engine side of the TB and has a forked clip that holds the front down, so you essentially tilt it down onto the stud and tighten it onto the motor. So, I made a gasket to fit underneath it since the rubber on the inside of the body of it seemed suspect. The gasket helped snug everything down nicely, I got the MAF tight and gave it a whirl. My STFT seems to stay around 3-4 on the Actron scanner, but will occasionally spike upward of 6 or 7 at idle. If I run the engine up to 2500rpm, I can see double digits pop up on the scanner before it levels itself off.
fuel pressure test
http://youtu.be/6TP49B2oWMoWell, no change, the code still comes on, but this time it came on while driving down the road. Haven’t got the specs on the freeze frame data, but it’s pretty much the same as before, with the exception of at speed and higher RPM.
I’m getting the smell of exhaust in the van if I crack the windows, which is more of a problem then anything. I can’t detect an audible exhaust leak at the engine or exhaust. I’m going to reset the fuel trim with our shop scanner on Monday and see if that gives me any different result.
On thing that did occur to me, I figured out where the thin spring probably came from. I had an issue with the IAC valve where I had pulled it and lost the small o ring for it. I had found it, but wanted to check the operation of the valve out of the engine. Turned on the ignition and the pintle flew out of it and across the engine to the passenger side of the van. I didn’t realize at the time that there might have been a spring in there as the pintle is moved within the IAC via a screw drive type of mechanism. I can only assume that that thin wire spring came out of that and landed on top of the manifold and I had just now found it. The van has idled just fine, but it took a few times of disconnecting the connection and cycling the key to get the pintle to move into the proper spot to get my idle down where it needed to be. However, I can’t test the operation of the IAC since I don’t have any way to put a load on the engine at idle ( no A/C ) and the last time I used Genisys OTC scanner, it didn’t respond to the commands from it. I don’t know if it’s at all related to my lean code being set or not as there is no issue with the idle and it’s been running this way for the last few months.
I’m not in the position to be throwing parts at the van and I don’t want to throw parts at the van to fix it. What I do know at this point is this:
The van ran fine, got 15.5ish mpg consistently.
I replaced the mechanical fan with an E fan and wired the relay to a KOKO source in the fuse panel under the hood of the van. In the process I also tried to tinker with the air filter set up as I currently have a cone style filter for my air filter and tried to see if I could find a way to get the stock airbox to work…which I did not…I put the air cleaner assembly that was on the van when I got it back on. IN the process of tinkering, I had bent the tabs that hold the air horn on the intake, to which I adjusted and reinstalled and verified the seal.
Shortly after finishing the wiring job and getting the van running again with the E fan, I started getting the P0171/174 lean bank codes and my mileage dropped to 14.5ish mpg over 2 tankfuls and I started smelling rich exhaust fumes in the van. The idle is stable, no fluctuations. Spraying around the intake, air horn and upper plenum areas did not change anything in the running condition of the van. It set the code just sitting still, Idleing and when I changed the exhaust donuts, the van idled fine, set no code, but as I drove down the road and the engine got up to operating temp to where the E fan should have kicked in, the code set.
Prior to this happening, the van ran flawlessly…no hiccups, no indications that something was wrong with the van.
The only other thing I can think to do is to wire the trigger 12v source up directly to the battery, but that means that the E fan will run with the key off if the thermostatic sensor still detects enough heat to trigger the fan. How long that could keep the fan running, I don’t know. If that’s what I end up having to do, then I guess that’s what I end up having to do.
I’m certainly open to suggestions on things to look at, inspect, test or probe. I just doesn’t seem probable to me that I suddenly developed an air leak to the point where I’m running unmetered air into the engine between the MAF and the O2 sensors seemingly overnight. Logically in my thinking, there either has to be something going on with the air horn or the breather hose coming from it to the passenger side valve cover, or there is something that is interfering with the computer electrically from the E fan that is causing a sensor to read out of range.
Oh, and no video fo the idler arm removal/installation…last minute weekend work that pressed me for time. Unfortunately, I still have a pull to the left even after replacing both idlers…the old ones seem to be in good shape still. I need to figure out what’s wrong with that still, but I’ll start another topic for that.
freeze frame data
P0174
TPS 0%
RPM 641
Cal Load 3.1
MAF .95
MAP 10.0 hg
coolant temp 174
LTFT1 19.5
STFT1 0.0
LTFT2 18.8
STFT2 -2.3I cleared the codes and drove the van up to operating temps and the light didn’t come on until I restarted the van after having breakfast with the wife for about 30 minutes.
It was a foggy morning at about 56F outdoor temps and we had had some precipitation the day before, the van ran the same as it has been. On the way back however, we started to smell the exhaust again about halfway back from where we were, about a 8 or 9 mile drive. Didn’t smell anything on the way there however. I’m beginning to wonder if it isn’t the exhaust donuts causing the problems. If both sides were leaking after they warmed up a bit, but leak at different rates, then it would make sense that we’d start to smell fuel as well as get the lean codes. I guess I’m going to replace the donuts just to be sure, since they are only about $12 and a half an hour to replace and we’ll see what happens.
