93 Jeep Grand Cherokee Cranks, But No Start
02-24-2006, 06:03 PM
#151
Guest
Posts: n/a
Re: 93 Jeep Grand Cherokee Cranks, But No Start
Casper did pass the time by typing:
> Thanks for the info. I am going to do a more testing this weekend.
No problem, hope it helps.
> Couple more questions...
>
> Should the fuel pressure be exactly 31psi? When we tested my
> neighbor's 95' GC Laredo, his was about 20-21Psi. We expected 30, but
> it only went up after starting, and then to about 40-41Psi.
31-32 is "normal" for the 4.0 engine, 39-40 is what happens when the vacuum
line is disconnected from the fuel rail regulator, and is a test for proper
function of the pressure regulator. A static (engine off) pressure of 20-21
is great. If you actually watch the pressure it will rise (quite a bit,
up to 50+) after a hot engine shutoff. Fuel is boiling in the injectors.
> He replaced his ECM last summer because he thought the tranny might be
> getting improper signals. As it turned out, one of the tranny
> connections had some broken magent pieces that were the culpprit to
> his gear switching issues. Once he cleaned that up, it shifts fine.
> But it may be that his starting problem began after he replaced the
> ECU. He plans on swapping the old ECU back in to test. He offered me
> his spare to test but not sure it would work in my 93'GC Limited.
95-96 was the change over to OBD-III diagnositcs, I can't say for certain
but if you get the part number off his ECU and take it to a dealer they
can tell you if it crosses years.
> And your website is cool. :-)
Thanks. :)
--
DougW
> Thanks for the info. I am going to do a more testing this weekend.
No problem, hope it helps.
> Couple more questions...
>
> Should the fuel pressure be exactly 31psi? When we tested my
> neighbor's 95' GC Laredo, his was about 20-21Psi. We expected 30, but
> it only went up after starting, and then to about 40-41Psi.
31-32 is "normal" for the 4.0 engine, 39-40 is what happens when the vacuum
line is disconnected from the fuel rail regulator, and is a test for proper
function of the pressure regulator. A static (engine off) pressure of 20-21
is great. If you actually watch the pressure it will rise (quite a bit,
up to 50+) after a hot engine shutoff. Fuel is boiling in the injectors.
> He replaced his ECM last summer because he thought the tranny might be
> getting improper signals. As it turned out, one of the tranny
> connections had some broken magent pieces that were the culpprit to
> his gear switching issues. Once he cleaned that up, it shifts fine.
> But it may be that his starting problem began after he replaced the
> ECU. He plans on swapping the old ECU back in to test. He offered me
> his spare to test but not sure it would work in my 93'GC Limited.
95-96 was the change over to OBD-III diagnositcs, I can't say for certain
but if you get the part number off his ECU and take it to a dealer they
can tell you if it crosses years.
> And your website is cool. :-)
Thanks. :)
--
DougW
02-24-2006, 06:03 PM
#152
Guest
Posts: n/a
Re: 93 Jeep Grand Cherokee Cranks, But No Start
Casper did pass the time by typing:
> Thanks for the info. I am going to do a more testing this weekend.
No problem, hope it helps.
> Couple more questions...
>
> Should the fuel pressure be exactly 31psi? When we tested my
> neighbor's 95' GC Laredo, his was about 20-21Psi. We expected 30, but
> it only went up after starting, and then to about 40-41Psi.
31-32 is "normal" for the 4.0 engine, 39-40 is what happens when the vacuum
line is disconnected from the fuel rail regulator, and is a test for proper
function of the pressure regulator. A static (engine off) pressure of 20-21
is great. If you actually watch the pressure it will rise (quite a bit,
up to 50+) after a hot engine shutoff. Fuel is boiling in the injectors.
> He replaced his ECM last summer because he thought the tranny might be
> getting improper signals. As it turned out, one of the tranny
> connections had some broken magent pieces that were the culpprit to
> his gear switching issues. Once he cleaned that up, it shifts fine.
> But it may be that his starting problem began after he replaced the
> ECU. He plans on swapping the old ECU back in to test. He offered me
> his spare to test but not sure it would work in my 93'GC Limited.
95-96 was the change over to OBD-III diagnositcs, I can't say for certain
but if you get the part number off his ECU and take it to a dealer they
can tell you if it crosses years.
> And your website is cool. :-)
Thanks. :)
--
DougW
> Thanks for the info. I am going to do a more testing this weekend.
No problem, hope it helps.
> Couple more questions...
>
> Should the fuel pressure be exactly 31psi? When we tested my
> neighbor's 95' GC Laredo, his was about 20-21Psi. We expected 30, but
> it only went up after starting, and then to about 40-41Psi.
31-32 is "normal" for the 4.0 engine, 39-40 is what happens when the vacuum
line is disconnected from the fuel rail regulator, and is a test for proper
function of the pressure regulator. A static (engine off) pressure of 20-21
is great. If you actually watch the pressure it will rise (quite a bit,
up to 50+) after a hot engine shutoff. Fuel is boiling in the injectors.
> He replaced his ECM last summer because he thought the tranny might be
> getting improper signals. As it turned out, one of the tranny
> connections had some broken magent pieces that were the culpprit to
> his gear switching issues. Once he cleaned that up, it shifts fine.
> But it may be that his starting problem began after he replaced the
> ECU. He plans on swapping the old ECU back in to test. He offered me
> his spare to test but not sure it would work in my 93'GC Limited.
95-96 was the change over to OBD-III diagnositcs, I can't say for certain
but if you get the part number off his ECU and take it to a dealer they
can tell you if it crosses years.
> And your website is cool. :-)
Thanks. :)
--
DougW
02-24-2006, 06:03 PM
#153
Guest
Posts: n/a
Re: 93 Jeep Grand Cherokee Cranks, But No Start
Casper did pass the time by typing:
> Thanks for the info. I am going to do a more testing this weekend.
No problem, hope it helps.
> Couple more questions...
>
> Should the fuel pressure be exactly 31psi? When we tested my
> neighbor's 95' GC Laredo, his was about 20-21Psi. We expected 30, but
> it only went up after starting, and then to about 40-41Psi.
31-32 is "normal" for the 4.0 engine, 39-40 is what happens when the vacuum
line is disconnected from the fuel rail regulator, and is a test for proper
function of the pressure regulator. A static (engine off) pressure of 20-21
is great. If you actually watch the pressure it will rise (quite a bit,
up to 50+) after a hot engine shutoff. Fuel is boiling in the injectors.
> He replaced his ECM last summer because he thought the tranny might be
> getting improper signals. As it turned out, one of the tranny
> connections had some broken magent pieces that were the culpprit to
> his gear switching issues. Once he cleaned that up, it shifts fine.
> But it may be that his starting problem began after he replaced the
> ECU. He plans on swapping the old ECU back in to test. He offered me
> his spare to test but not sure it would work in my 93'GC Limited.
95-96 was the change over to OBD-III diagnositcs, I can't say for certain
but if you get the part number off his ECU and take it to a dealer they
can tell you if it crosses years.
> And your website is cool. :-)
Thanks. :)
--
DougW
> Thanks for the info. I am going to do a more testing this weekend.
No problem, hope it helps.
> Couple more questions...
>
> Should the fuel pressure be exactly 31psi? When we tested my
> neighbor's 95' GC Laredo, his was about 20-21Psi. We expected 30, but
> it only went up after starting, and then to about 40-41Psi.
31-32 is "normal" for the 4.0 engine, 39-40 is what happens when the vacuum
line is disconnected from the fuel rail regulator, and is a test for proper
function of the pressure regulator. A static (engine off) pressure of 20-21
is great. If you actually watch the pressure it will rise (quite a bit,
up to 50+) after a hot engine shutoff. Fuel is boiling in the injectors.
> He replaced his ECM last summer because he thought the tranny might be
> getting improper signals. As it turned out, one of the tranny
> connections had some broken magent pieces that were the culpprit to
> his gear switching issues. Once he cleaned that up, it shifts fine.
> But it may be that his starting problem began after he replaced the
> ECU. He plans on swapping the old ECU back in to test. He offered me
> his spare to test but not sure it would work in my 93'GC Limited.
95-96 was the change over to OBD-III diagnositcs, I can't say for certain
but if you get the part number off his ECU and take it to a dealer they
can tell you if it crosses years.
> And your website is cool. :-)
Thanks. :)
--
DougW
02-25-2006, 10:32 AM
#154
Guest
Posts: n/a
Re: 93 Jeep Grand Cherokee Cranks, But No Start (0/1)
>On Fri, 24 Feb 2006 15:51:05 -0500, Mike Romain wrote:
>You can post photos over in alt.binaries.pictures.autos.4x4 if your
>server carries that newsgroup. It is pretty empty and a bunch of us
>post there. I use Sony's imagestation site for my off road albums.
Just got thru posting them there. I will check out the Sony site.
Thanks for the info!
>I am not likely the same Mike because I have no idea where Six Flags
>is....
Six Flags is all over. Multiple theme parks across the US. They are
second to Disney. But if you've never heard of them...
different Mike... but nice to meet you!
>Good luck,
Thanks again!
~Casper <Jeepers... It's a Jeep thing!>
>You can post photos over in alt.binaries.pictures.autos.4x4 if your
>server carries that newsgroup. It is pretty empty and a bunch of us
>post there. I use Sony's imagestation site for my off road albums.
Just got thru posting them there. I will check out the Sony site.
Thanks for the info!
>I am not likely the same Mike because I have no idea where Six Flags
>is....
Six Flags is all over. Multiple theme parks across the US. They are
second to Disney. But if you've never heard of them...
different Mike... but nice to meet you!
>Good luck,
Thanks again!
~Casper <Jeepers... It's a Jeep thing!>
02-25-2006, 10:32 AM
#155
Guest
Posts: n/a
Re: 93 Jeep Grand Cherokee Cranks, But No Start (0/1)
>On Fri, 24 Feb 2006 15:51:05 -0500, Mike Romain wrote:
>You can post photos over in alt.binaries.pictures.autos.4x4 if your
>server carries that newsgroup. It is pretty empty and a bunch of us
>post there. I use Sony's imagestation site for my off road albums.
Just got thru posting them there. I will check out the Sony site.
Thanks for the info!
>I am not likely the same Mike because I have no idea where Six Flags
>is....
Six Flags is all over. Multiple theme parks across the US. They are
second to Disney. But if you've never heard of them...
different Mike... but nice to meet you!
>Good luck,
Thanks again!
~Casper <Jeepers... It's a Jeep thing!>
>You can post photos over in alt.binaries.pictures.autos.4x4 if your
>server carries that newsgroup. It is pretty empty and a bunch of us
>post there. I use Sony's imagestation site for my off road albums.
Just got thru posting them there. I will check out the Sony site.
Thanks for the info!
>I am not likely the same Mike because I have no idea where Six Flags
>is....
Six Flags is all over. Multiple theme parks across the US. They are
second to Disney. But if you've never heard of them...
different Mike... but nice to meet you!
>Good luck,
Thanks again!
~Casper <Jeepers... It's a Jeep thing!>
02-25-2006, 10:32 AM
#156
Guest
Posts: n/a
Re: 93 Jeep Grand Cherokee Cranks, But No Start (0/1)
>On Fri, 24 Feb 2006 15:51:05 -0500, Mike Romain wrote:
>You can post photos over in alt.binaries.pictures.autos.4x4 if your
>server carries that newsgroup. It is pretty empty and a bunch of us
>post there. I use Sony's imagestation site for my off road albums.
Just got thru posting them there. I will check out the Sony site.
Thanks for the info!
>I am not likely the same Mike because I have no idea where Six Flags
>is....
Six Flags is all over. Multiple theme parks across the US. They are
second to Disney. But if you've never heard of them...
different Mike... but nice to meet you!
>Good luck,
Thanks again!
~Casper <Jeepers... It's a Jeep thing!>
>You can post photos over in alt.binaries.pictures.autos.4x4 if your
>server carries that newsgroup. It is pretty empty and a bunch of us
>post there. I use Sony's imagestation site for my off road albums.
Just got thru posting them there. I will check out the Sony site.
Thanks for the info!
>I am not likely the same Mike because I have no idea where Six Flags
>is....
Six Flags is all over. Multiple theme parks across the US. They are
second to Disney. But if you've never heard of them...
different Mike... but nice to meet you!
>Good luck,
Thanks again!
~Casper <Jeepers... It's a Jeep thing!>
02-25-2006, 10:32 AM
#157
Guest
Posts: n/a
Re: 93 Jeep Grand Cherokee Cranks, But No Start (0/1)
>On Fri, 24 Feb 2006 15:51:05 -0500, Mike Romain wrote:
>You can post photos over in alt.binaries.pictures.autos.4x4 if your
>server carries that newsgroup. It is pretty empty and a bunch of us
>post there. I use Sony's imagestation site for my off road albums.
Just got thru posting them there. I will check out the Sony site.
Thanks for the info!
>I am not likely the same Mike because I have no idea where Six Flags
>is....
Six Flags is all over. Multiple theme parks across the US. They are
second to Disney. But if you've never heard of them...
different Mike... but nice to meet you!
>Good luck,
Thanks again!
~Casper <Jeepers... It's a Jeep thing!>
>You can post photos over in alt.binaries.pictures.autos.4x4 if your
>server carries that newsgroup. It is pretty empty and a bunch of us
>post there. I use Sony's imagestation site for my off road albums.
Just got thru posting them there. I will check out the Sony site.
Thanks for the info!
>I am not likely the same Mike because I have no idea where Six Flags
>is....
Six Flags is all over. Multiple theme parks across the US. They are
second to Disney. But if you've never heard of them...
different Mike... but nice to meet you!
>Good luck,
Thanks again!
~Casper <Jeepers... It's a Jeep thing!>
02-25-2006, 01:41 PM
#158
Guest
Posts: n/a
Re: 93 Jeep Grand Cherokee Cranks, But No Start
DougW did pass the time by typing:
> Casper did pass the time by typing:
>>> "DougW" did pass the time by typing:
>>> The ECU (engine brain) is what does all the testing and lights the Check
>>> Engine light.
>>
>> Oh, the only two engine codes that show up are 12 and 55. I've been
>> checking those about every three to four days and no changes.
>> Unfortunately I do not have an ODBC checker to connect to my PC.. tho
>> I am giving it some serious thought as of late. Thanks again!
>
> The 93's diagnosic system is OBD-III, not OBD-III compliant, so the
oops.. the 93 is OBD-II, not III
> modern code scanners don't work.. You have to buy a $peical one from
> one of a few vendors.
> Casper did pass the time by typing:
>>> "DougW" did pass the time by typing:
>>> The ECU (engine brain) is what does all the testing and lights the Check
>>> Engine light.
>>
>> Oh, the only two engine codes that show up are 12 and 55. I've been
>> checking those about every three to four days and no changes.
>> Unfortunately I do not have an ODBC checker to connect to my PC.. tho
>> I am giving it some serious thought as of late. Thanks again!
>
> The 93's diagnosic system is OBD-III, not OBD-III compliant, so the
oops.. the 93 is OBD-II, not III
> modern code scanners don't work.. You have to buy a $peical one from
> one of a few vendors.
02-25-2006, 01:41 PM
#159
Guest
Posts: n/a
Re: 93 Jeep Grand Cherokee Cranks, But No Start
DougW did pass the time by typing:
> Casper did pass the time by typing:
>>> "DougW" did pass the time by typing:
>>> The ECU (engine brain) is what does all the testing and lights the Check
>>> Engine light.
>>
>> Oh, the only two engine codes that show up are 12 and 55. I've been
>> checking those about every three to four days and no changes.
>> Unfortunately I do not have an ODBC checker to connect to my PC.. tho
>> I am giving it some serious thought as of late. Thanks again!
>
> The 93's diagnosic system is OBD-III, not OBD-III compliant, so the
oops.. the 93 is OBD-II, not III
> modern code scanners don't work.. You have to buy a $peical one from
> one of a few vendors.
> Casper did pass the time by typing:
>>> "DougW" did pass the time by typing:
>>> The ECU (engine brain) is what does all the testing and lights the Check
>>> Engine light.
>>
>> Oh, the only two engine codes that show up are 12 and 55. I've been
>> checking those about every three to four days and no changes.
>> Unfortunately I do not have an ODBC checker to connect to my PC.. tho
>> I am giving it some serious thought as of late. Thanks again!
>
> The 93's diagnosic system is OBD-III, not OBD-III compliant, so the
oops.. the 93 is OBD-II, not III
> modern code scanners don't work.. You have to buy a $peical one from
> one of a few vendors.
02-25-2006, 01:41 PM
#160
Guest
Posts: n/a
Re: 93 Jeep Grand Cherokee Cranks, But No Start
DougW did pass the time by typing:
> Casper did pass the time by typing:
>>> "DougW" did pass the time by typing:
>>> The ECU (engine brain) is what does all the testing and lights the Check
>>> Engine light.
>>
>> Oh, the only two engine codes that show up are 12 and 55. I've been
>> checking those about every three to four days and no changes.
>> Unfortunately I do not have an ODBC checker to connect to my PC.. tho
>> I am giving it some serious thought as of late. Thanks again!
>
> The 93's diagnosic system is OBD-III, not OBD-III compliant, so the
oops.. the 93 is OBD-II, not III
> modern code scanners don't work.. You have to buy a $peical one from
> one of a few vendors.
> Casper did pass the time by typing:
>>> "DougW" did pass the time by typing:
>>> The ECU (engine brain) is what does all the testing and lights the Check
>>> Engine light.
>>
>> Oh, the only two engine codes that show up are 12 and 55. I've been
>> checking those about every three to four days and no changes.
>> Unfortunately I do not have an ODBC checker to connect to my PC.. tho
>> I am giving it some serious thought as of late. Thanks again!
>
> The 93's diagnosic system is OBD-III, not OBD-III compliant, so the
oops.. the 93 is OBD-II, not III
> modern code scanners don't work.. You have to buy a $peical one from
> one of a few vendors.
