BobLoblaw Posted December 22, 2008 Share Posted December 22, 2008 (edited) I started my 94 Pathy XE this morning to warm it up; leaving it in neutral. Everything seemed alright. 10 mins later, I went to back it out (in 4WH) and it stalled. When I tried to restart it, it wouldn't go. I popped the hood, checked to see if anything was leaking or any smells - none. Then I tried to start it again, it fired up - blowing a huge cloud of dark smoke out the exhaust. I was so happy that it started as I had to get to work.....until I tried to back it out again. STALL. Left it for a few mins / started it / tried to drive it forward back into my parking spot - STALL. So it will idle, but stall if regular gas pedal pressure is given, or alternatively, will almost stall then rev very high if I just stomp on the gas while trying to move forward or backward. I went behind the truck and pushed it back into the spot. That's when I noticed a gas smell; either gas ot some very rich exhaust (it was belching smoke after all). It seemed to be coming from the back end somewhere. It has been really cold here for a couple weeks (-20 -30 C). What does this problem sound like to you? My first guess was fuel pump, but I'm not sure. Edited December 22, 2008 by BobLoblaw Link to comment Share on other sites More sharing options...
here4now Posted December 22, 2008 Share Posted December 22, 2008 my guess is that your idle is too low, and that you'll need to figure out where to get a 3rd foot from until it's fixed. Link to comment Share on other sites More sharing options...
Indigent Posted December 22, 2008 Share Posted December 22, 2008 (edited) From the FSM EF & EC-14: "The IACV-air regulator provides an air by-pass when the engine is cold for a fast idle during warm up." I had that problem a while back. It is pretty easy to check. Take the cable off and check the resistance across the two contacts of the regulator. It should be between 70-80 ohms. Even if it checks out OK, it could still be clogged. It is held in with two 10mm bolts that are fairly easy to get to (no plenum removal required), and then one of those stupid Nissan hose clamps that can be a moderate pain. There is an O-ring that seals it to the plenum that can wear out (don't remember the diameter). All said, it should take you no more than about 30 minutes to pull the regulator and test it out. I am always about testing the cheapest things first, and as this will not *cost* anything to check, it can't hurt. Hope this helps, indigent. Edited December 22, 2008 by Indigent Link to comment Share on other sites More sharing options...
BobLoblaw Posted December 22, 2008 Author Share Posted December 22, 2008 (edited) From the FSM EF & EC-14:"The IACV-air regulator provides an air by-pass when the engine is cold for a fast idle during warm up." I had that problem a while back. It is pretty easy to check. Take the cable off and check the resistance across the two contacts of the regulator. It should be between 70-80 ohms. Even if it checks out OK, it could still be clogged. It is held in with two 10mm bolts that are fairly easy to get to (no plenum removal required), and then one of those stupid Nissan hose clamps that can be a moderate pain. There is an O-ring that seals it to the plenum that can wear out (don't remember the diameter). All said, it should take you no more than about 30 minutes to pull the regulator and test it out. I am always about testing the cheapest things first, and as this will not *cost* anything to check, it can't hurt. Hope this helps, indigent. Thanks for your help! Do you have any pics of the location of this regulator, or a precise description of where it is? I'm not going to be able to find this on my own. Do I need a volt meter to do this? I don't have one.....yet. Will any generic o-ring do? Does anyone know the diameter? This problem is a crippling blow to me at this time of the year; I'm stranded!!! Edited December 23, 2008 by BobLoblaw Link to comment Share on other sites More sharing options...
Indigent Posted December 23, 2008 Share Posted December 23, 2008 You will definitely need a multimeter. Hopefully the attached pic will help you. It is on the driver's side of the plenum. It almost looks like a little cone sticking up with a wire harness attached to the top of it. Check www.phatg20.net for a copy of the FSM. It is very handy to have around. Remember, this could very well not be what's wrong. I would start with the multimeter and check the regulator out electrically. hope this helps. indigent. Link to comment Share on other sites More sharing options...
BobLoblaw Posted December 23, 2008 Author Share Posted December 23, 2008 You will definitely need a multimeter. Hopefully the attached pic will help you. It is on the driver's side of the plenum. It almost looks like a little cone sticking up with a wire harness attached to the top of it. Check www.phatg20.net for a copy of the FSM. It is very handy to have around. Remember, this could very well not be what's wrong. I would start with the multimeter and check the regulator out electrically. hope this helps. indigent. I really appreciate your help man. Thanks for the pic. I found it but haven't taken it off yet. It's pretty busy around here these days! As a update of sorts, I let the Pathy run until it got warm and the stalling went away. I had the hood open and just kept revving it a little and eventually it was just like normal. It's sounds like it probably is the part you said, indigent. At autozone these IACV-air regulators are $130-160 US!! Maybe someone here has a spare working one.....or this one could be fixed! Does this part only function in the extreme cold? Oh yeah, and the phatg20.net site doesn't work for me. Did it move? Is the manual a .pdf file you could send me? Thanks again. Merry Christmas. Link to comment Share on other sites More sharing options...
here4now Posted December 23, 2008 Share Posted December 23, 2008 I really appreciate your help man. Thanks for the pic. I found it but haven't taken it off yet. It's pretty busy around here these days! As a update of sorts, I let the Pathy run until it got warm and the stalling went away. I had the hood open and just kept revving it a little and eventually it was just like normal. It's sounds like it probably is the part you said, indigent. At autozone these IACV-air regulators are $130-160 US!! Maybe someone here has a spare working one.....or this one could be fixed! Does this part only function in the extreme cold? Oh yeah, and the phatg20.net site doesn't work for me. Did it move? Is the manual a .pdf file you could send me? Thanks again. Merry Christmas. send me your email address and I can shot you over a copy. btw the valve only lists for $104 at the dealer Link to comment Share on other sites More sharing options...
Precise1 Posted December 24, 2008 Share Posted December 24, 2008 It has been really cold here for a couple weeks (-20 -30 C). HOLY CRAP!! Could be that the valve is just sticking/frozen due to the temp? I know I would be... If you do need to replace it, check out the classified section here; there are always people parting out trucks... B Link to comment Share on other sites More sharing options...
Indigent Posted December 24, 2008 Share Posted December 24, 2008 You don't have to remove the whole regulator to check it out electrically. I would at least check the resistance first, then if that checks out OK, take it apart. indigent. Link to comment Share on other sites More sharing options...
shack Posted December 25, 2008 Share Posted December 25, 2008 send me your email address and I can shot you over a copy. btw the valve only lists for $104 at the dealer Can you shoot me a copy of that manual too? darrin_shacklett@yahoo.com I am pretty new to the Pathfinder scene and mine has quite a few problems. I am sure this manual would come in handy. I have a 94 SE model Link to comment Share on other sites More sharing options...
here4now Posted December 25, 2008 Share Posted December 25, 2008 Can you shoot me a copy of that manual too? darrin_shacklett@yahoo.com I am pretty new to the Pathfinder scene and mine has quite a few problems. I am sure this manual would come in handy. I have a 94 SE model http://rapidshare.com/files/45424771/1994_Pathfinder.zip PW = pdftown.com Link to comment Share on other sites More sharing options...
94extreme Posted December 26, 2008 Share Posted December 26, 2008 CEL light on? o2 sensor? Link to comment Share on other sites More sharing options...
Indigent Posted December 26, 2008 Share Posted December 26, 2008 One thing that really bothers me about the ECU in these things is that not all sensors and electronics are part of the CEL routine. The idle air control valve and regulator are among those. Two pretty important parts, but not monitored for failure at all. BTW that is a good point; did you run through ECU diagnostics? indigent. Link to comment Share on other sites More sharing options...
BobLoblaw Posted December 26, 2008 Author Share Posted December 26, 2008 One thing that really bothers me about the ECU in these things is that not all sensors and electronics are part of the CEL routine. The idle air control valve and regulator are among those. Two pretty important parts, but not monitored for failure at all. BTW that is a good point; did you run through ECU diagnostics? indigent. No I did not - I've never done it before. As soon as the temp gets a little warmer, I'll try it with the instructions in the 'garage' forum. BTW, what is 'CEL'? Is there a chance the IACV is just stuck and needs a good whack to loosen it up? Link to comment Share on other sites More sharing options...
Indigent Posted December 26, 2008 Share Posted December 26, 2008 CEL is check engine light. Did you ever check the resistance between the two contacts of the regulator? I am all about hitting things to try to get them to work. Just dont hit the plastic part too hard lol. indigent. Link to comment Share on other sites More sharing options...
BobLoblaw Posted December 31, 2008 Author Share Posted December 31, 2008 CEL is check engine light. Did you ever check the resistance between the two contacts of the regulator? I am all about hitting things to try to get them to work. Just dont hit the plastic part too hard lol. indigent. No, I haven yet. My bad. the holiday season is so busy. Here is the volt meter I am looking at: http://www.canadiantire.ca/browse/product_...fromSearch=true If there is a better one, please let me know, especially if it is cheaper! This might sound daft but once a get this meter, how do I properly test the current. I want to at least do it properly!! Link to comment Share on other sites More sharing options...
KLL Posted December 31, 2008 Share Posted December 31, 2008 is your car idles and revs when engine is cold? and if it happens when it is warm, this is possibly caused by oxygen sensors. if there is rich gasoline smell at exhaust this is another proof. Link to comment Share on other sites More sharing options...
BobLoblaw Posted January 1, 2009 Author Share Posted January 1, 2009 is your car idles and revs when engine is cold? and if it happens when it is warm, this is possibly caused by oxygen sensors. if there is rich gasoline smell at exhaust this is another proof. It idles fine all the time. It revs fine for about 5-10 secs after initial startup, then begins to do this stall-out when the gas is pushed until the engine is warm. Funny you should mention that (the rich smell), because I have been getting about 200km per tank these days; I was getting 350km before winter/this idle problem. I expect to lose some fuel economy in winter and using 4wd but that is ridiculous. I replace the water temp sensor so I know it's not that. I hoping to attempt a code retrieval after New Years when it is supposed to get warmer. Car problems are killing me right now; I have a Maxima that is screwing with me too! Happy New Year Everyone! Link to comment Share on other sites More sharing options...
Kittamaru Posted January 1, 2009 Share Posted January 1, 2009 It idles fine all the time. It revs fine for about 5-10 secs after initial startup, then begins to do this stall-out when the gas is pushed until the engine is warm. Funny you should mention that (the rich smell), because I have been getting about 200km per tank these days; I was getting 350km before winter/this idle problem. I expect to lose some fuel economy in winter and using 4wd but that is ridiculous. I replace the water temp sensor so I know it's not that. I hoping to attempt a code retrieval after New Years when it is supposed to get warmer. Car problems are killing me right now; I have a Maxima that is screwing with me too!Happy New Year Everyone! Same here with the Fuel Mileage... except mine went from around 325 to around 225 Mpg, not Kpg... o0' Link to comment Share on other sites More sharing options...
veilside180sx Posted January 4, 2009 Share Posted January 4, 2009 (edited) To me what you are describing would be a bad maf (mass airflow sensor). The ecu is set to bypass the maf if it is not functioning properly and run in limp mode. The ecu is not capable of handling any load w/o it though, so it'll run rich and choke if you press the gas hard. The maf bypass setup would let the car run, but fall on it's face when the gas is pressed. It's basically just meant for limping home. The IACV is considered to not be functioning properly if the idle falls over 50 rpms outside it's specified range. These rarely go wrong, but do get a fair amount of carbon build up. If you remove the sensor there is two parts. Unbolt the electrical portion and clean the left over carbon build up out with brake cleaner. Edited January 5, 2009 by veilside180sx Link to comment Share on other sites More sharing options...
BobLoblaw Posted January 5, 2009 Author Share Posted January 5, 2009 (edited) To me what you are describing would be a bad maf (mass airflow sensor). The ecu is set to bypass the maf if it is not functioning properly and run in limp mode. The ecu is not capable of handling any load w/o it though, so it'll run rich and choke if you press the gas hard. The maf bypass setup would let the car run, but fall on it's face when the gas is pressed. It's basically just meant for limping home. The IACV is considered to not be functioning properly if the idle falls over 50 rpms outside it's specified range. These rarely go wrong, but do get a fair amount of carbon build up. If you remove the sensor there is two parts. Unbolt the electrical portion and clean the left over carbon build up out with brake cleaner. Once the pathy is warm, it doesn't hesitate anymore. It drives regularly, except it is too rich (does feel like 'limp' mode once it's warm). Could it still be a MAS? Are those relatively easy to replace? Also, are you talking about removing the Mass air flow sensor and cleaning it with brake cleaner or the IACV? Edited January 5, 2009 by BobLoblaw Link to comment Share on other sites More sharing options...
veilside180sx Posted January 5, 2009 Share Posted January 5, 2009 (edited) Once the pathy is warm, it doesn't hesitate anymore. It drives regularly, except it is too rich (does feel like 'limp' mode once it's warm). Could it still be a MAS? Are those relatively easy to replace? Also, are you talking about removing the Mass air flow sensor and cleaning it with brake cleaner or the IACV? IACV with brake cleaner. The fact that your car only does it when cold, would lead me more to the IACV than the maf. The maf is more susceptible to dirt than carbon buildup, since it's before the intake manifold and the air is flowing the other way through it. The maf is really easy to pull off. It's right next to the air box. The maf is basically a thermistor. The air flowing over it cools the thermistor down, and the ecu compensates based the reading. The more air that flows over it, the more fuel the ecu feeds through the injectors. Has your ecu thrown any codes? Do you happen to have a K&N filter, or another oil based filter element? Edited January 5, 2009 by veilside180sx Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now