From owner-xj-digest-at-digest.net Thu Nov 5 16:05:38 2009 From: xj-digest xj-digest Friday, November 6 2009 Volume 01 : Number 3097 Forum for Discussion of XJ cherokees and wagoneers Brian Colucci Digest Coordinator Contents: xj: '89 4.0L/Renix not running, not starting xj: crank position sensor info Re: xj: '89 4.0L/Renix not running, not starting Re: xj: crank position sensor info XJ Digest Home Page: http://www.digest.net/jeep/xj/ Send submissions to xj-digest-at-digest.net Send administrative requests to xj-digest-request-at-digest.net To unsubscribe, include the word unsubscribe by itself in the body of the message, unless you are sending the request from a different address than the one that appears on the list. Include the word help in a message to xj-digest-request to get a list of other majordomo commands. ---------------------------------------------------------------------- Date: Thu, 5 Nov 2009 15:39:57 -0800 (PST) From: john Subject: xj: '89 4.0L/Renix not running, not starting yes earnest, my bad, it's a 1989 Cherokee with the 4.0L/Renix system. PCM? are you talking about the computer under the dash? the jeep is 50 miles away... the guy said it quit running while driving and would not restart... he's back east dealing with a family emergency but seemed to think it was the TPS or trans computer, which shouldn't kill it dead. The CPS will cause stalling and misfires, but I've not seen one kill it dead... but it's possible, and WILL be looked at. The MAP sensor seems to be the primary suspect... if it's spark related. If it's fuel related the pump/filter seems to be high on the list of probables. later I'll compose some step by steps from everyone's input and see if we have everything nailed, will grab a few parts at lunch tomorrow and then go down on Saturday to get it going. :) john ----- - ------------------------------------------------------------------------ Snohomish, Washington -o|||||o- where Jeeps don't rust, they mold http://AMSOIL.com/redirect.cgi?zo=283461 http://creationwiki.org http://johnmeister.com http://wagoneers.com http://fotomeister.us - ------------------------------------------------------------------------ On Thu, 5 Nov 2009, ernest breakfield wrote: # it's not clear what year (or even which motor) we're talking about,but # lets ASSuME that this is an older 4.0 (since we're talking about a # separate Trans Computer) and that the No-Start is a crank but won't fire # as opposed to won't even turn over. # # in that case, i can't see how it could be the TPS or the Trans # Computer; neither should cause a No-Run situation. # starting simple; do we know it even has fuel and hasn't just been # run out of gas? # is the fuel good? # is the fuel filter clogged? # after that, first step in the General Diagnostic Procedure (at least # in my FSM from the mid-90s) is to check and clean the PCM mounting bolt, # as it supplies the electrical ground for the PCM. # do we have any idea if it cranks and doesn't fire at all, or if it's # hitting occasionally but not 'catching'? knowing what kind of No-Start # we're dealing with would help a lot with a keyboard diagnosis,... ;-) # # beyond that, *which* CPS you're talking about can make a difference # in Failure Modes (as there were at least 2 different suppliers for later # years; i'm not sure how many for earlier years). # CPS Failure Mode can be: # - dies while running and may restart (usually for a short period of time # before the failure becomes more permanent), or # - gets increasingly harder to start until it just plain *won't* start. # # without a CPS signal to the PCM, i believe you won't have fuel # injector signals or spark, though you should be able to occasionally # still hear the fuel pump run briefly to pressurize the system at key-on. # (the fuel pump could be easily verified by releasing the pressure on the # fuel rail before key-on just to make sure it needs to bring it up to # pressure.) # # # cheers! # e # # # diesel john wrote: # > don't know what the exact symptoms are, it's not here, going down Saturday... # > # > it was running, then died, couldn't get it started again... no other details, PO thinks it was # > the TPS and/or the automatic trans computer... he's in TX right now, medical/family emergency, left # > it about a month ago, will be back there for months... his daughter is selling it... # > # > going to bring a MAP, CPS, TPS... anything else that would kill it while it's running and not start it again? # > # > cps will stall, but it'll restart # > tps will make it run crappy... # > # > map will kill it dead and not start it, right? # > # > I've got some test stuff on XJ/tech - reorganized the directories to clean them up... old files will NOT be found from # > book marks, also renamed them to make more sense, I hope. ;) # > # > john # > # > # > # > ----- # > ------------------------------------------------------------------------ # > Snohomish, Washington -o|||||o- where Jeeps don't rust, they mold # > http://AMSOIL.com/redirect.cgi?zo=283461 http://creationwiki.org # > http://johnmeister.com http://wagoneers.com http://fotomeister.us # > ------------------------------------------------------------------------ # ------------------------------ Date: Thu, 5 Nov 2009 15:47:33 -0800 (PST) From: john Subject: xj: crank position sensor info ouch... here's the updated page info: http://wagoneers.com/XJ/tech/WIRING/CrankPositionSensor/ALL.html and some info from Alan Chung: http://wagoneers.com/XJ/tech/WIRING/starting-problems.html ----- - ------------------------------------------------------------------------ Snohomish, Washington -o|||||o- where Jeeps don't rust, they mold http://AMSOIL.com/redirect.cgi?zo=283461 http://creationwiki.org http://johnmeister.com http://wagoneers.com http://fotomeister.us - ------------------------------------------------------------------------ On Thu, 5 Nov 2009, Don Hansen wrote: # It's ALWAYS the CPS!!! # Sometimes unplugging/re-plugging the CPS will get it to start. # # I once dropped a socket and swivel down the CPS hole! Let me tell you how # much fun I had getting that sucker out from flex-plate land!!! # # -Don # # -------------------------------------------------- # From: "ernest breakfield" # Sent: Thursday, November 05, 2009 4:20 PM # To: # Subject: Re: xj: RE: fsj: Diesel + Jeep = popcorn adventure # # > it's not clear what year (or even which motor) we're talking about,but # > lets ASSuME that this is an older 4.0 (since we're talking about a # > separate Trans Computer) and that the No-Start is a crank but won't fire # > as opposed to won't even turn over. # > # > in that case, i can't see how it could be the TPS or the Trans # > Computer; neither should cause a No-Run situation. # > starting simple; do we know it even has fuel and hasn't just been # > run out of gas? # > is the fuel good? # > is the fuel filter clogged? # > after that, first step in the General Diagnostic Procedure (at least # > in my FSM from the mid-90s) is to check and clean the PCM mounting bolt, # > as it supplies the electrical ground for the PCM. # > do we have any idea if it cranks and doesn't fire at all, or if it's # > hitting occasionally but not 'catching'? knowing what kind of No-Start # > we're dealing with would help a lot with a keyboard diagnosis,... ;-) # > # > beyond that, *which* CPS you're talking about can make a difference # > in Failure Modes (as there were at least 2 different suppliers for later # > years; i'm not sure how many for earlier years). # > CPS Failure Mode can be: # > - dies while running and may restart (usually for a short period of time # > before the failure becomes more permanent), or # > - gets increasingly harder to start until it just plain *won't* start. # > # > without a CPS signal to the PCM, i believe you won't have fuel # > injector signals or spark, though you should be able to occasionally # > still hear the fuel pump run briefly to pressurize the system at key-on. # > (the fuel pump could be easily verified by releasing the pressure on the # > fuel rail before key-on just to make sure it needs to bring it up to # > pressure.) # > # > # > cheers! # > e # > # > # > diesel john wrote: # > > don't know what the exact symptoms are, it's not here, going down # > > Saturday... # > > # > > it was running, then died, couldn't get it started again... no other # > > details, PO thinks it was # > > the TPS and/or the automatic trans computer... he's in TX right now, # > > medical/family emergency, left # > > it about a month ago, will be back there for months... his daughter is # > > selling it... # > > # > > going to bring a MAP, CPS, TPS... anything else that would kill it while # > > it's running and not start it again? # > > # > > cps will stall, but it'll restart # > > tps will make it run crappy... # > > # > > map will kill it dead and not start it, right? # > > # > > I've got some test stuff on XJ/tech - reorganized the directories to # > > clean them up... old files will NOT be found from # > > book marks, also renamed them to make more sense, I hope. ;) # > > # > > john # > > # > > # > > # > > ----- # > > ------------------------------------------------------------------------ # > > Snohomish, Washington -o|||||o- where Jeeps don't rust, they mold # > > http://AMSOIL.com/redirect.cgi?zo=283461 http://creationwiki.org # > > http://johnmeister.com http://wagoneers.com http://fotomeister.us # > > ------------------------------------------------------------------------ ------------------------------ Date: Thu, 05 Nov 2009 16:04:12 -0800 From: ernest breakfield Subject: Re: xj: '89 4.0L/Renix not running, not starting hi John! (it's 'ernest', not eArnest; no matter what spellcheck tells us.) ;-) PCM; FSM-speak for Powertrain Control Module. (in my '94, it's on the left front fender,... but there's no separate Trans computer either,...) by CPS i mean Crankshaft Position Sensor, not Camshaft Position Sensor. OK; i'm admittedly not intimately familiar with the Renix stuff. i'm not certain if a lack of signal from the CPS on the Renix units will cut out spark and injectors as it will with the later models, but would suspect it's the same. odds are if you have spark, it's not the CPS. 'quit while driving and not wanting to restart' could be lots of different things, but that's exactly the way mine failed when my CPS went out; no warning like stalling or misfiring whatsoever. might be different for the Renix units, but i had several friends (with later models) whose CPSs failed in one of the 2 modes i described earlier; in both cases, they would crank fine, but not spark,... until suddenly they did. (usually this failure to run would last just about as long as it would take to unplug and replug the wires, so i was always suspicious as to whether or not unplug/reconnecting them would have any real effect... but have read reports that some people have allegedly "cured" their CPS problems by just wrapping the connector tighter with baling wire.) mine failed while running several times like someone had just flipped off a switch, with increasing reluctance to restart until the CPS was replaced... FWIW, i do remember noticing that the tach would drop like a stone to zero when it was failing, but don't know if the Renix stuff has the same symptom. but we still don't have enough info to be able to know if that's this guys problem or not. cheers! e john wrote: > yes earnest, my bad, it's a 1989 Cherokee with the 4.0L/Renix system. > > PCM? are you talking about the computer under the dash? > > the jeep is 50 miles away... the guy said it quit running while driving and would not > restart... he's back east dealing with a family emergency but seemed to think it > was the TPS or trans computer, which shouldn't kill it dead. > > The CPS will cause stalling and misfires, but I've not seen one kill it dead... but it's > possible, and WILL be looked at. > > The MAP sensor seems to be the primary suspect... if it's spark related. > > If it's fuel related the pump/filter seems to be high on the list of probables. > > > later I'll compose some step by steps from everyone's input and see if we have > everything nailed, will grab a few parts at lunch tomorrow and then go down on > Saturday to get it going. :) > > john > > ----- > ------------------------------------------------------------------------ > Snohomish, Washington -o|||||o- where Jeeps don't rust, they mold > http://AMSOIL.com/redirect.cgi?zo=283461 http://creationwiki.org > http://johnmeister.com http://wagoneers.com http://fotomeister.us > ------------------------------------------------------------------------ > > > On Thu, 5 Nov 2009, ernest breakfield wrote: > > # it's not clear what year (or even which motor) we're talking about,but > # lets ASSuME that this is an older 4.0 (since we're talking about a > # separate Trans Computer) and that the No-Start is a crank but won't fire > # as opposed to won't even turn over. > # > # in that case, i can't see how it could be the TPS or the Trans > # Computer; neither should cause a No-Run situation. > # starting simple; do we know it even has fuel and hasn't just been > # run out of gas? > # is the fuel good? > # is the fuel filter clogged? > # after that, first step in the General Diagnostic Procedure (at least > # in my FSM from the mid-90s) is to check and clean the PCM mounting bolt, > # as it supplies the electrical ground for the PCM. > # do we have any idea if it cranks and doesn't fire at all, or if it's > # hitting occasionally but not 'catching'? knowing what kind of No-Start > # we're dealing with would help a lot with a keyboard diagnosis,... ;-) > # > # beyond that, *which* CPS you're talking about can make a difference > # in Failure Modes (as there were at least 2 different suppliers for later > # years; i'm not sure how many for earlier years). > # CPS Failure Mode can be: > # - dies while running and may restart (usually for a short period of time > # before the failure becomes more permanent), or > # - gets increasingly harder to start until it just plain *won't* start. > # > # without a CPS signal to the PCM, i believe you won't have fuel > # injector signals or spark, though you should be able to occasionally > # still hear the fuel pump run briefly to pressurize the system at key-on. > # (the fuel pump could be easily verified by releasing the pressure on the > # fuel rail before key-on just to make sure it needs to bring it up to > # pressure.) > # > # > # cheers! > # e > # > # > # diesel john wrote: > # > don't know what the exact symptoms are, it's not here, going down Saturday... > # > > # > it was running, then died, couldn't get it started again... no other details, PO thinks it was > # > the TPS and/or the automatic trans computer... he's in TX right now, medical/family emergency, left > # > it about a month ago, will be back there for months... his daughter is selling it... > # > > # > going to bring a MAP, CPS, TPS... anything else that would kill it while it's running and not start it again? > # > > # > cps will stall, but it'll restart > # > tps will make it run crappy... > # > > # > map will kill it dead and not start it, right? > # > > # > I've got some test stuff on XJ/tech - reorganized the directories to clean them up... old files will NOT be found from > # > book marks, also renamed them to make more sense, I hope. ;) > # > > # > john > # > > # > > # > > # > ----- > # > ------------------------------------------------------------------------ > # > Snohomish, Washington -o|||||o- where Jeeps don't rust, they mold > # > http://AMSOIL.com/redirect.cgi?zo=283461 http://creationwiki.org > # > http://johnmeister.com http://wagoneers.com http://fotomeister.us > # > ------------------------------------------------------------------------ > # ------------------------------ Date: Thu, 05 Nov 2009 16:06:17 -0800 From: ernest breakfield Subject: Re: xj: crank position sensor info wasn't Alans XJ non-Renix? would his info apply? cheers! e john wrote: > ouch... > > here's the updated page info: > http://wagoneers.com/XJ/tech/WIRING/CrankPositionSensor/ALL.html > > and some info from Alan Chung: > http://wagoneers.com/XJ/tech/WIRING/starting-problems.html > > > > ----- > ------------------------------------------------------------------------ > Snohomish, Washington -o|||||o- where Jeeps don't rust, they mold > http://AMSOIL.com/redirect.cgi?zo=283461 http://creationwiki.org > http://johnmeister.com http://wagoneers.com http://fotomeister.us > ------------------------------------------------------------------------ > > > On Thu, 5 Nov 2009, Don Hansen wrote: > > # It's ALWAYS the CPS!!! > # Sometimes unplugging/re-plugging the CPS will get it to start. > # > # I once dropped a socket and swivel down the CPS hole! Let me tell you how > # much fun I had getting that sucker out from flex-plate land!!! > # > # -Don > # > # -------------------------------------------------- > # From: "ernest breakfield" > # Sent: Thursday, November 05, 2009 4:20 PM > # To: > # Subject: Re: xj: RE: fsj: Diesel + Jeep = popcorn adventure > # > # > it's not clear what year (or even which motor) we're talking about,but > # > lets ASSuME that this is an older 4.0 (since we're talking about a > # > separate Trans Computer) and that the No-Start is a crank but won't fire > # > as opposed to won't even turn over. > # > > # > in that case, i can't see how it could be the TPS or the Trans > # > Computer; neither should cause a No-Run situation. > # > starting simple; do we know it even has fuel and hasn't just been > # > run out of gas? > # > is the fuel good? > # > is the fuel filter clogged? > # > after that, first step in the General Diagnostic Procedure (at least > # > in my FSM from the mid-90s) is to check and clean the PCM mounting bolt, > # > as it supplies the electrical ground for the PCM. > # > do we have any idea if it cranks and doesn't fire at all, or if it's > # > hitting occasionally but not 'catching'? knowing what kind of No-Start > # > we're dealing with would help a lot with a keyboard diagnosis,... ;-) > # > > # > beyond that, *which* CPS you're talking about can make a difference > # > in Failure Modes (as there were at least 2 different suppliers for later > # > years; i'm not sure how many for earlier years). > # > CPS Failure Mode can be: > # > - dies while running and may restart (usually for a short period of time > # > before the failure becomes more permanent), or > # > - gets increasingly harder to start until it just plain *won't* start. > # > > # > without a CPS signal to the PCM, i believe you won't have fuel > # > injector signals or spark, though you should be able to occasionally > # > still hear the fuel pump run briefly to pressurize the system at key-on. > # > (the fuel pump could be easily verified by releasing the pressure on the > # > fuel rail before key-on just to make sure it needs to bring it up to > # > pressure.) > # > > # > > # > cheers! > # > e > # > > # > > # > diesel john wrote: > # > > don't know what the exact symptoms are, it's not here, going down > # > > Saturday... > # > > > # > > it was running, then died, couldn't get it started again... no other > # > > details, PO thinks it was > # > > the TPS and/or the automatic trans computer... he's in TX right now, > # > > medical/family emergency, left > # > > it about a month ago, will be back there for months... his daughter is > # > > selling it... > # > > > # > > going to bring a MAP, CPS, TPS... anything else that would kill it while > # > > it's running and not start it again? > # > > > # > > cps will stall, but it'll restart > # > > tps will make it run crappy... > # > > > # > > map will kill it dead and not start it, right? > # > > > # > > I've got some test stuff on XJ/tech - reorganized the directories to > # > > clean them up... old files will NOT be found from > # > > book marks, also renamed them to make more sense, I hope. ;) > # > > > # > > john > # > > > # > > > # > > > # > > ----- > # > > ------------------------------------------------------------------------ > # > > Snohomish, Washington -o|||||o- where Jeeps don't rust, they mold > # > > http://AMSOIL.com/redirect.cgi?zo=283461 http://creationwiki.org > # > > http://johnmeister.com http://wagoneers.com http://fotomeister.us > # > > ------------------------------------------------------------------------ ------------------------------ End of xj-digest V1 #3097 *************************