Help, 97 Jeep Tj Code P1494 ... 4 years and 2 mechanics, still can't find problem - JeepForum.com
 3Likes
  • 3 Post By TheBoogieman
 
LinkBack Thread Tools
post #1 of 11 Old 12-03-2014, 07:40 PM Thread Starter
racertracer
Registered User
2005 KJ Liberty 
 
Join Date: Jul 2005
Posts: 11
Help, 97 Jeep Tj Code P1494 ... 4 years and 2 mechanics, still can't find problem

Need help with this issue that I have been experiencing for 4 years now. I don't drive the Jeep as much as I used to and it's parked outside. I mostly drive it during the winter months.

I need to get rid of this engine light to pass inspection and get it registered again.

P1494 Leak detection pump or mechanical fault, I just can't find the problem and the 1997 doesn't have a leak detection pump, I've been told.

Smoke test was performed recently and couldn't detect the leak.

Did the following:

1. Replaced charcoal canister
2, Replaced throttle body,
3. inspected all vacuum hoses in the engine compartment and those leading to the tank.
any ideas?

racertracer is offline  
Sponsored Links
Advertisement
 
post #2 of 11 Old 12-03-2014, 07:50 PM
Dave02TJ
Registered User
 
Dave02TJ's Avatar
2002 TJ Wrangler 
 
Join Date: Nov 2013
Location: Crystal Lake
Posts: 1,490
Is the PCM the original PCM?

Did 97 Tj's have the ability to throw that code? See if it's on the list for 97's specifically.
Dave02TJ is offline  
post #3 of 11 Old 12-04-2014, 01:08 AM
Knuckelhead
R.I.P. Knuckelhead
 
Knuckelhead's Avatar
2000 TJ Wrangler 
 
Join Date: Aug 2005
Location: Colorado
Posts: 21,946
Did you try a new gas cap?...

Gone but not forgotten.
Knuckelhead is offline  
 
post #4 of 11 Old 12-04-2014, 01:16 AM Thread Starter
racertracer
Registered User
2005 KJ Liberty 
 
Join Date: Jul 2005
Posts: 11
Quote:
Originally Posted by Dave02TJ View Post
Is the PCM the original PCM?

Did 97 Tj's have the ability to throw that code? See if it's on the list for 97's specifically.
Not sure if it is the original 1997 PCM.


Do you know if there is a web site with the list of codes for the 1997?

Yes replaced the gas cap.
racertracer is offline  
post #5 of 11 Old 12-04-2014, 02:00 AM
Dave02TJ
Registered User
 
Dave02TJ's Avatar
2002 TJ Wrangler 
 
Join Date: Nov 2013
Location: Crystal Lake
Posts: 1,490
Quote:
Originally Posted by racertracer View Post
Not sure if it is the original 1997 PCM.


Do you know if there is a web site with the list of codes for the 1997?

Yes replaced the gas cap.
http://www.jeep4x4center.com/knowledge-base/

Not exactly a list.

I looked for you and do not see that code listed for 1997 model year.
If you look under 1997 under the fuel system *edit-"wiring/emissions" they show the evaporitive emissions in that section. Normally that info would be found in the emissions section, as it is in the 1998 manual.
*sorry, it is under "wiring/emissions"
I wish I had a paper copy of a 97 manual to be more thorough.

In 1998 that code existed and it can be found in the manual.

As far as I am aware the 1997 models did not have a leak detection pump.
I have seen 3 different styles of evaporative emissions on Wranglers.

You may want to verify your PCM's part number to see if it is for a 97.

Or I could be completely off It just strikes me odd for you to have that code.

*** I' not sure if there was a California emissions 97 wrangler that is different, maybe someone from California knows that? California is a whole different world to me lol.


Your Jeep is a 97 correct ?
Dave02TJ is offline  
post #6 of 11 Old 02-09-2016, 07:25 PM
Sudcalifornio
Registered User
 
Sudcalifornio's Avatar
2002 TJ Wrangler 
 
Join Date: Jan 2013
Location: Riverbank
Posts: 216
Garage
had the same code found a leak in the intake manifold gasket
Sudcalifornio is offline  
post #7 of 11 Old 02-10-2016, 03:07 AM
Jonny Jeep
Web Wheeler
 
Jonny Jeep's Avatar
1997 TJ Wrangler 
 
Join Date: Feb 2007
Location: Manchester
Posts: 6,814
There were no leak detection pumps on 97s, so P1494 is not a code that should crop up. I would assume it has been replaced with a 98 or 99 PCM. As Dave02TJ suggests you should verify the PCM part number.

If it turns out it is a PCM from a 98 or 99 you will have two options. Either find a 97 PCM to replace it, or replace the emissions canister with one from a 98 or later model, add the leak detection pump which is bolted to it by a bracket, and add the wiring to the LDP to the relevant pins in the PCM connectors.

If you can get pins to add to the PCM connectors the second option might be better as a quick look on ebay shows the later canisters with LDP can be bought pretty cheap. This one is complete with the connector to the LDP which you could run wires from...
http://www.ebay.com/itm/1998-02-Jeep...id=p5731.m3795

Edit: I'm also wondering if the PCM could be fooled into thinking there is no leak. I'll need to look into this and see what input the PCM is looking for. If it is a steady state you may just need to supply a voltage or ground to the LDP switch input of the PCM. Might not get back to this before work so you may have to wait for more info on that possible option.
- scratch that. It's too complicated to fool as it looks for changes in the O2 output as part of it's checks and if it doesn't see any it assumes the evap solenoid isn't working so you'd get a code for that instead.

Options as I see it are as I've stated above.
Jonny Jeep is offline  
post #8 of 11 Old 09-17-2021, 10:51 AM
tjswenson
Registered User
 
Join Date: Oct 2017
Posts: 1
My 1997 ZJ is California spec and DOES have a vapor leak detection pump.
tjswenson is offline  
post #9 of 11 Old 09-22-2021, 11:30 PM
TheBoogieman
Disturbed Jeepaholic
 
TheBoogieman's Avatar
2003 TJ Wrangler 
 
Join Date: Aug 2006
Location: charlottesHELL
Posts: 41,470
Quote:
Originally Posted by tjswenson View Post
My 1997 ZJ is California spec and DOES have a vapor leak detection pump.
02-10-2016.

Only 5 years late responding.
jgarden, numchuck and tr21triton like this.

Quote:
Originally Posted by jeepinmichguy_ View Post
TheBoogieman is a jerk.
2003' Rubicon/Zone 4.25" combo lift with Rancho RS5000X shocks/ Zone hydro shocks/5.13 gears/35" Mickey Thompson MTZ P3 tires/Black Magic brakes. Jeep #17 & 19.
TheBoogieman is offline  
post #10 of 11 Old 09-23-2021, 04:48 AM
jtec
Registered User
 
jtec's Avatar
2014 JK Wrangler 
 
Join Date: Oct 2017
Posts: 10,556
this is interesting-

BASICS -
what is the 8th and the 10th character of your vin#?
tyr taking the codes using key on key off trick. Post all codes.
Can you see any #s on PCM?

When I see the price of OEM I think aftermarket.
When I see the quality of aftermarket I think OEM.
jtec is offline  
post #11 of 11 Old 10-04-2021, 04:27 AM
PDoyle
Registered User
 
PDoyle's Avatar
2003 TJ Wrangler 
 
Join Date: Apr 2006
Location: Saratoga Springs NY
Posts: 935
Quote:
Originally Posted by TheBoogieman View Post
02-10-2016.

Only 5 years late responding.
Starting to see alot of old threads popping up. I think we're getting older and cant see the post dates

2003 X, 5 speed, FT/RR bumpers by Eddie Reighard. JKS 1" body lift, JKS disco's, 2 1/2" Rough Country lift, 8k Warn, w/class 3 receiver FT & RR hitch. GA 8 rims riding 33's- GY Kevlar.
SOLD- 1985 CJ7 soft top , fiberglass body, 5" total lift258-6- Howell TBI, Full Roll cage.
PDoyle is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome