Bump, just looking for input. Could the stock air box not being on this car, and instead an after market air filter, cause an issue like this?
#1
Hey guys,I've got a '98 GTI VR6 throwing this code, and I've read up on it as much as I can find. I understand that the Intake air temp sensor is separate from the MAF on this engine, and after talking to someone it sounds like it's not usual that the IAT would go bad, so it could be a wiring issue. So, I'm wondering if anyone out there can clue me into if they've had this issue, and what they've done to fix it. I don't really want to have the mechanic run diagnostics on the car, but I also don't currently have a Bentley for this car, so I have no wiring diagrams. I'm in a rock and a hard place because I can't get the car past emissions without clearing this code out.
So, has anyone else had this, and fixed it? Please share. The posts I've found on here have been mostly inconclusive and usually lead to the MAF, but that doesn't seem right to me considering it's the IAT, so here I am asking.
Also, semi related, does anyone have a scan of the fuse box layout and/or wiring diagrams to this engine? I have yet to find any of this on the vortex.
Thanks.
Modified by botkiller at 9:34 PM 12-2-2009
#2
Bump, just looking for input. Could the stock air box not being on this car, and instead an after market air filter, cause an issue like this?
#3
http://diyrabbit.com/projects/vagcom/
step8... !!!
here you go ..!!
wher to buy it :
http://www.mjmautohaus.com/cat...=2246
for the MKIV .. the IAT is the MAF ....![]()
#4
Quote, originally posted by sebich1 » http://diyrabbit.com/projects/vagcom/
step8... !!!
here you go ..!!
wher to buy it :
http://www.mjmautohaus.com/cat...=2246
for the MKIV .. the IAT is the MAF ....![]()
Ok, this is very useful. Thank you! I'm going to check that IAT as soon as I have a chance. I'm also buying my vag.com cable NOW, as I need this thing badly.
I think on the Jetta MKIII, the IAT is the MAF, as well. Seems on the 98 GTI it's a separate thing.
Thank you for your help; this means a lot.
#5
i am glad to help when i can !!
good luck man ..and keep us posted !!![]()
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#6
Well, I replaced the IAT, and the code is still there. I took the battery off for awhile, the code didn't clear, and I can't delete the code myself, as I only have the shareware VAGCOM. I understand that the code should disappear when the issue is fixed, but it is my experience that that doesn't always work. At that, I have NO friggin' clue what else to do here. The wiring I can trace looks fine, no breaks. The connectors are clean. The ****ing code is still there, and keeping me from getting this ****ing car past emissions and getting it registered. I'm extremely stressed about this right now, because my only other thought can be that there is a throttle body issue, an issue with the ECM, or some other cryptic **** that I can't figure out.If anyone's got any ideas, I could really use them. Right now this car is a lump of metal in my driveway that's starting to piss me off more every day because of one stupid ass OBD code that wont' go away.
#7
Also, WTF is this connector (see below pic)? This thing looks like it come out of the harness that's on the coilpack that then runs to the big mas of wires on the right side of the engine, which I assume then goes to the ECM eventually. Thing is, there is NO PLACE for this to connect to; I have stuck my head everywhere I can to find a place for it, and I see no open port for it. Being that p0113 is for an open circuit, I'm weary of anything sitting there not connected to anything.... so does anyone know where the hell this thing goes? The wire colors on it are red and black and yellow and brown, it's a two port plug. It definitely looks like it goes to a sensor or something of the like, and it's short, so its got to go to something very near to it. I'd really love some thoughts, I'mright now.
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#8
check the intake manifold right above the FPR, thats the IAT
Modified by sun98gtiVR6 at 3:49 PM 12-21-2009
#9
FPR? please define.
I have replaced the IAT - I used this as a guide:http://diyrabbit.com/projects/vagcom/
After testing the IAT and seeing that it didn't have any output, I got a new one off germanautoparts.com and replaced it. took the battery off for an hour or so, restarted the car, scanned the codes with vagcom, and the code is still there. I'm wondering what that connector is, because it sure as hell seems it should be connected to something...
#10
FPR=fuel pressure regulatorthe iat threads into the intake, and faces the drivers side
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#11
Quote, originally posted by sun98gtiVR6 » FPR=fuel pressure regulator the iat threads into the intake, and faces the drivers side
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Right, this is the IAT:
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Which I replaced.
Where is the FPR, then? I don't see anything for this to connect to. Does anyone have pics of the FPR?
#12
PS, someone at the Bentley forums says that the connector I'm wondering about is for a water pump. It can't be THE water pump, as near as I can tell, so now I'm just even more confused.... this car is a headache.
#13
They're talking about the secondary water pump, which attaches to the same bracket as that large twist connector in your picture. Your hand kinda covers it up, but it looks like you may not have one installed. Previous owner may have deleted it, as they are known to fail, be pretty expensive, and not do a whole lot under normal driving conditions. Zip tie the connector out of the way?
For best results, experience reality in moderation.
#14
Quote, originally posted by benny_mech » They're talking about the secondary water pump, which attaches to the same bracket as that large twist connector in your picture. Your hand kinda covers it up, but it looks like you may not have one installed. Previous owner may have deleted it, as they are known to fail, be pretty expensive, and not do a whole lot under normal driving conditions. Zip tie the connector out of the way? Sounds like that's the case. Ok, so, I still have this code, then, and can't get rid of the damn thing. Thoughts? I thought this connector could be related, but now assume it is not. Back to square A. Other thoughts on how to clear this stupid PITA code?
#15
I have also taken the round wiring harness at the right of the engine apart and looked for corrosion, there is nothing, the connectors all look good from what I can see. Anything else I should look for?
#16
Ok, a few things here, after having been away from this for a week or so:1. After I disconnected the wiring harness, the car wouldn't start correctly. I removed the harness again and reconnected it, and it started fine; I can only assume that I hadn't gotten the harness back on entirely, therefore making an issue.
2. After all of this, I ran vagcom again. It pulled a ton of codes; p1240, 1241, 1242, 1237, 1238, 1239. These are all listed as open circuits on the fuel injectors on each cylinder. Again, I can only assume that these are because the harness wasn't connected right; if the circuits were open on all of these injectors, the car wouldn't even turn over.
3. I purchased an inova code scanner and just got it in the mail today; I scanned and it found these codes again. I deleted the codes, because I've never seen them before as it is. Now, I notice that the middle spark plug on the bottom row of cylinders is arcing; I can see it if I look at the engine running in the dark. As near as I can tell, the others are not. I am going to replace the plug, if it still arcs, I'll replace the wire. I had seen this spark plug arcing previously, and planned to replace it, but the IAT has been the primary issue as of right now.
4. The CEL in this car has seemingly stopped working. It worked when the car was first purchased, clicking on/off when the car was started. However, now, it doesn't light up at all. I can only assume that the CEL bulb is burnt out, which is just fabulous. The Inova scanner shows the CEL as being lit when its connected to the car.
All I can think now is to replace the spark plug and possibly the wire, and drive the car as much as possible, and rescan the codes, seeing what is sticking. I know that the CEL needs to be fixed, but I can't do that myself. I simply do not have the energy nor time right now to take this car's console apart. I'll go to a mechanic for that function, but I'd first like to figure out the rest of this bull, if possible.
I thank you guys for your input, I will work to test the IAT wiring and such as mentioned a few posts ago, although I'm not entirely sure how to do that, to be honest. I have read posts by others that issues like this have been cleared after redoing the plugs/wires; I know I have to fix the arcing plug anyway, so perhaps it will have a good affect on things.
#18
I had an issue with that on my 1.8T and it turned out there was a break in the wiring on that sensor. You gotta run the wires and figure out from there. Pain in the ass but it beats spending money on the sensor.
#19
Quote, originally posted by teknoracing » I had an issue with that on my 1.8T and it turned out there was a break in the wiring on that sensor. You gotta run the wires and figure out from there. Pain in the ass but it beats spending money on the sensor. The sensor was only $20. I replaced it, and I still have the same issue, so I guess it could be the wiring. However, I'm still confused about this OBD drive cycle bull****, and why these other codes aren't clearing, even though I cleared the damn codes with the scanner. I've been driving the car around for awhile now, just running it, hoping that the computer will snap awake and stop being a little bitch.
PS, does anyone have a DIY on how to remove the cluster to replace bulbs in it? Thanks.
#20
Good luck, i replace the sensor and thats how i assumed i had to check the wires.
#21
Well, I've replaced the sensor, and the wiring all looks ok, I have yet to trace it back to the ECM, checking for breaks all the way, but everything I can see looks ok, yet, it still throws the code.I'm about to give up, and take a shotgun to this car.
#22
Hi everyone,OK, so I got the cluster off, bought the stupid $5 bulb, and replaced the CEL, so now I know it's on, all the time, of course.
Now, in trying to figure this code out, I've decided to put a stock airbox back on, as I have read that having the aftermarket intake can cause this code.
I've put the box in, but here's what I can't figure out... what hose is supposed to connect to the top front of the box, as seen in this image:
What I figure is that it's supposed to connect to a hose that comes of the front of the engine that I can see near the middle front, below the headers, just behind the cooling fan, which it looks like the past owner did a rather ghetto job on; you can see (very sparingly) in this picture where there is a wire mesh over the hose that I refer to:
So what I'm wondering is, should I get a length of tubing and run it from this to the front of the airbox? It seems odd that it would come out of the engine and into the airbox, but this seems the only likely candidate, and considering it's got the mesh over it, I can only assume that it's a rigging job done to keep the flow of air open, but put the aftermarket intake on. I also know that there shouldn't be an open port on the top front of the airbox, of course, because that's unfiltered air going into the MAF. Also, I don't see how this hose would have been routed from the engine to the airbox; it would have to pass right over the alternator, and seems, well, not right; but all the same, I am only now getting to know the VR6 engine, coming from 2.0 land, after all.
I should also mention I cleaned the crap out of the MAF while I had everything off (using MAF cleaner, of course).
Anyone got thoughts? All the intake info I find is for aftermarket, and that's not what I need, right now.
Any help is appreciated, thanks!
Modified by botkiller at 9:37 PM 1-31-2010
#23
Anyone? bumpa lumpa.
#24
looks like the previous owner deleted the secondary air injection on the car. the secondary air is used to add extra o2 to the motor to help the oxidizing cataylst u r probably getting that p0113 because of that btw i looked up that code p0113 it reads02 sensor circuit slow response. I would try using a dso and add propane to the intake and watch the respose rate of the 02 sensor it should go full rich or above .975mv when the propane is introduced and when u take it away and snap the throttle it should go back to lean again or no less than .100m and the response time should be 100ms or less if not u have a lazy 02 sensor. i would try hooking back up the secondary air pump and clear code and see wut happens then i would go the dso propane method to chk 02 sensor response rate good luck![]()
#25
u ever figure that thing out???
#26
Thanks for all the info there man!
Ok, so here's where I'm at now with this fsacking car...This car has driven me up a wall. I haven't yet put a hose between the secondary air and the airbox (although there is a filter on that secondary air pump, albeit not a great one), but I did just take it into a shop here - I'm having anxiety attacks about this car at this point, and it's not even mine (it's my girlfriend's)!
The shop called me and told me that the wiring harness at the back of the engine (the circular one) has some blown pins on it, and that it would be best to replace the harness. That part, of course, is $440
I don't believe that these guys are trying to rip me off; this car obviously has issues talking to the ECU.
The basic idea right now is that the harness isn't talking to the ECU right, which I would believe, considering I can't get the codes to clear off the engine.
So, where I'm at now, is I either replace that harness, and connect the secondary air to the airbox and hope to god that all of this clears up, or, I wait, and keep digging on the car, although I'm literally at the end of my noose here. I've done everything on this thing that I can relatively do, and I'm running out of options, time, sanity, and hair.
So I guess what I need to figure out is, should I blow the money on a new harness in hopes of it working (or does anyone have one of these for sale), should I spend more time on the car myself (doing what, I don't know, I'm not a car electrical guy), or should I just kiss this car goodbye and part it/sell it and cut my losses? It appears to run fine, but these codes and that CEL causing me to not be able to register it make it pretty much a useless automobile to me.
I'd love thoughts ASAP, because I'll likely pull the trigger on getting it worked on tomorrow (2/24).
*sigh*. Thanks guys...
Modified by botkiller at 6:11 PM 2-23-2010
#30