Is the under hood emissions sticker accurate?

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indio

TJ Enthusiast
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Is the emissions sticker found under the TJ hood 100% accurate for the given vehicle, or more of a generic sticker for the year?

Reason I ask, is a previous owner of my 1998 TJ removed the Evap Canister (and possibly the Leak Detection Pump) that are typically mounted on the driver side fender. My TJ only has the Duty Cycle Purge Solenoid.

I highlighted in yellow the three key components in the photo of my TJ sticker. The problem is, based on research and advice from forum members, the 1998 model year had different emissions configurations, depending on if it was early in the year, and depending on if it was Federal or California designated. Some 1998 TJs had a Leak Detection Pump, while others did not.

You can see my TJ sticker also indicates California. So would I be correct to assume based on the sticker diagram, that my TJ came with the Leak Detection Pump?

1998TjEmissionsSticker_v02.jpg


1998TjEmissionsSticker_v01.jpg
 
I was under the impression all TJs were 50 state emission vehicles. Is that wrong?
 
Chris said:
I was under the impression all TJs were 50 state emission vehicles. Is that wrong?
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Based on some online research, people are saying there is California and what they call Federal emissions equipment on various TJs. And I have seen some photos of emissions stickers from TJs online that seems to back that up. Mainly some emissions stickers do not mention California. Also some emissions sticker diagrams do not include the Leak Detection Pump in the sticker diagram.

Forum member Jerry mentioned on his 1997 TJ, there is no Leak Detection Pump. So it seems like at least in the earlier years of the TJ, some might have had the pump, and some might not. And also the Evap Canister seems to have changed design.

I'm finding the situation confusing, and I can't simply rely on engine photos, as they appear to differ in 1998. Maybe I should go by the emission sticker diagram under my hood. In that case I would need to source a Leak Detection Pump, Evap Cansiter, and related bracketry. And actually these are available second hand, but what confuses me is, the pump appears to have an electrical connector, and I'm not sure how that would work with my TJ.
 
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indio said:
I'm finding the situation confusing, and I can't simply rely on engine photos, as they appear to differ in 1998.
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I'm already confused, so you're not alone.

Here's a question (and pardon me if I missed the answer), but why does it matter? Are you getting error codes saying that something is missing or are you unable to pass emissions?

If so, then I get it, but if not, then I would say just forget about the whole thing in general.
 
Chris said:
I'm already confused, so you're not alone.

Here's a question (and pardon me if I missed the answer), but why does it matter? Are you getting error codes saying that something is missing or are you unable to pass emissions?

If so, then I get it, but if not, then I would say just forget about the whole thing in general.
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I do get a code: P1494. Engine seemed to be running fine with that code. I live in Chicagoland and we have an emissions test, so I knew eventually I would need to get that code sorted out (figured vacuum leak), but was in no hurry.

Then a few days ago my TJ started having an idle problem, every few seconds changing idle speed. That's when I started looking under the hood, and realized hey, the evap canister is missing.

Also muddying the waters, the idle issue started occurring around the time I swapped the stock fuel cap for an aftermarket locking cap. Sadly I am still trying to find where I put the stock cap, so I can swap back and see if the idle problem goes away.

Regardless, the P1494 code was occurring before I change the fuel cap. Bottom line: if the idle issue doesn't go away and because of the code, I am wanting to find out exactly what my TJ came with in terms of emissions equipment, and probably restore that functionality, in case it will fix the code and down the road allow the TJ to pass emissions.
 
Here's a question then. Have you found any extra plugs or connectors where something might actually be missing?
 
Chris said:
Here's a question then. Have you found any extra plugs or connectors where something might actually be missing?
Click to expand...

I did find two unused electrical plugs in same area as the emissions components. I'll look closer and post a photo tomorrow, in case anyone can identify those plugs.
 
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P1494 means your leak detection pump is not working. It doesn't mean you have a leak, it means the pump, lines or wiring are damaged. I think a 1998 has a leak detection pump, you need to find it and have a look. At least that's what I'd do.
 
pagrey said:
P1494 means your leak detection pump is not working. It doesn't mean you have a leak, it means the pump, lines or wiring are damaged. I think a 1998 has a leak detection pump, you need to find it and have a look. At least that's what I'd do.
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Some 1998 TJs had a Leak Detection Pump, and some did not. It depends on if the TJ was an early 1998 model, and if it was built to California emissions spec. But based on the under hood emissions sticker on my TJ (see earlier photo in this thread), I am suspecting my TJ originally had a Leak Detection Pump, and a previous owner removed it. That would explain the P1494 code - because the pump is no longer there.
 
indio said:
I did find two unused electrical plugs in same area as the emissions components. I'll look closer and post a photo tomorrow, in case anyone can identify those plugs.
Click to expand...

That might help. Admittedly I'm not going to be of much help since I don't have a TJ at the moment, and I never had a 98. I also thought they all had 50 state emissions to be honest.

However, those missing connectors might allow someone else to say, "Hey, that connector on my TJ is going to _______". Know what I mean?
 
In terms of unused connections under the hood, here are some photos of what I found. Maybe someone with a 1998 or similar TJ can verify if these connectors are used or not?:

The following two female connectors are laying unused, on the empty tray on drivers side of engine bay near firewall (not sure what if anything is supposed to be on that tray):
UnusedConnectors.jpg


Here is a closeup of the two connectors. One has 2 female electrical ports, the other 8 ports:
UnusedConnectorsCloseUp.jpg


Also there is a plugged vacuum port on the manifold. I've seen photos of other TJs having this port plugged (although with a black not red plug). I think this port is used if a TJ has a Leak Detection Pump. So maybe this red cap was installed by previous owner, if he removed the Leak Detection Pump:
ManifoldPortPlug.jpg
 
mots said:
One thing is certain, if you are throwing p1494, then your PCM is coded for a Leak Detection Pump and the PCM expects it to be plugged in and functioning.

Here is a Dorman unit that is fairly cheap...I bet OEM is going to be twice that easy.

https://www.rockauto.com/en/catalog...st+&+emission,vapor+leak+detection+pump,12040
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I'm suspecting you are correct. The problem, if you look at the Dorman LDP (see photo below), it has a 3 prong electrical connector. But if you look at the two unused electrical connectors I found in my TJ engine bay, they do not seem to match this Dorman 3 prong male connector:

Dorman LDP:
DormanLeakDetectionPump.jpg


Two unused electrical connections under my TJ hood (in same area where this pump would be located):
UnusedConnectorsCloseUp.jpg
 
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indio said:
I'm suspecting you are correct. The problem, if you look at the Dorman LDP (see photo below), it has a 3 prong electrical connector. But if you look at the two unused electrical connectors I found in my TJ engine bay, they do not seem to match this Dorman 3 prong male connector:

Dorman LDP:
View attachment 97287

Two unused electrical connections under my TJ hood (in same area where this pump would be located):
View attachment 97288
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Nice of them to make it so easy for the end user. Probably threw things together from multiple sources to meet CA emission rules. Perhaps you can find a unit for an older or newer TJ year that fits your harness. You could potentially throw a resistor in there to make the PCM “think” it is there, but I wouldn’t have any good advise on where to start with that or if it would have a good chance to work in this case. Best bet is to find a pump, even if from a junk yard.
 
My 98 is an se 2.5 instead of the 4.0 so things are probably different, but i took some pics anyway.

Sticker
97367


Overall
?hash=33452eb0fb0e5983a2b8bd197e7aac31.jpg


Connector 1, brakes
97369


Connector 2, headlights, horn, etc. Up in the front right corner.
97370


Connector 3. The pump right next to what appears to be a schrader valve cap that says something about evap, 1 psi max.
97372


20190601_171118.jpg
 
just looked at the pic of my sticker and it looks like no test pump, only a purge solenoid. I guess none of that was helpful.
 
A leak detection pump will not have a connection to the intake manifold, that makes no sense. I guess sometimes Chrysler makes no sense but I can't see a reason for that.
 
dudehitt said:
just looked at the pic of my sticker and it looks like no test pump, only a purge solenoid. I guess none of that was helpful.
Click to expand...

No problem, I appreciate your photos and info. Your TJ confirms what I've been reading. Namely, your emissions sticker does not mention California, and your emissions sticker diagram does not have a Leak Detection Pump. At least on the earlier TJs, seems like California/LDP are synonymous.
 
An update: I found a guy on ebay selling a used evap assembly for my California emissions 1998 TJ. Below is a photo of the installed assembly. With this assembly I now have the missing Evap Canister and Leak Detection Pump. I was able to get everything connected, in terms of the vacuum hoses and electrical.

Good news - the p1494 code for missing Leak Detection Pump is gone (because I now have one!). And the TJ now runs smoother, and the idle is improved. Used to be too high and jump around under certain conditions.

However the PCM is throwing a Pending Code P0455. My understanding - this is for a "large evap leak". Typically a gas cap leak or evap rubber hose leak. I'm going to drive it a bit more and see if code goes away, given it is a "pending" code.

One thing - has anyone found a replacement for the little right angle hoses (shown in red circles)? These are degraded, and I'd like to replace in case they are leaking and contributing to the P0455. But I was not able to find at Pepboys the other day, maybe there is some other good source for these?

EVAPEmmissionsElbowHoses.jpg
 
A little smear of clear silicon over those should seal up any small leaks. I would call this a "temporary " fix.
 
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