Fuel smell and bad mileage

[Jeepmedic46]

When I start up my 2000 Jeep Cherokee there is a strong fuel smell. The Jeep was at the dealer for the 4WD linkage. When they started it if it was something bad would they have said something about it? What would cause the smell of fuel and my gas mileage is horrible. Not able to tell the exact mileage but the gas gauge is going down. It’s a replacement engine the previous owner put in.

 

[Boostpowered]

Is the smell coming out of your tailpipe or in the cab? If out the exhaust id say your running rich for some reason. if its in cabin id begin checking all the fuel hoses and fittings pronto. Have you scraped on anything? Possible fuel tank puncture or cut line.

 

[Jeepmedic46]

Jeep hasn’t run over anything or scraped against anything. I’ll check in the morning to see if it’s coming out of the tailpipe. I think the Jeep might be running rough.

 

[Boostpowered]

If your getting the strong fuel smell and bad mileage id check all the fuel lines and fittings first off. Start and run it for a few seconds letting it idle and leak if its gonna then check turn off so you see fresh wetness. Above anything else your engine may be doing this is a safety issue first. Unless your engine is carbeurated its not normal to smell fuel from the tailpipe of a fuel injected vehicle unless youve got a bad injector or possibly a bad o2 sensor but i would check lines first.

 

[Jeepmedic46]

If your getting the strong fuel smell and bad mileage id check all the fuel lines and fittings first off. Start and run it for a few seconds letting it idle and leak if its gonna then check turn off so you see fresh wetness. Above anything else your engine may be doing this is a safety issue first. Unless your engine is carbeurated its not normal to smell fuel from the tailpipe of a fuel injected vehicle unless youve got a bad injector or possibly a bad o2 sensor but i would check lines first.

Not seeing any wetness under the vehicle and not seeing any wetness on the fuel lines. Will check them out again. Could the engine catch on fire. It just left the dealer after they worked on the 4WD. You would have thought they would have caught it.

 

[Jeepmedic46]

I hate not being more mechanically inclined and not having anyone near me that I can trust. I want to learn but never have had the chance. Sorry just ranting

 

[Josh56]

I hate not being more mechanically inclined and not having anyone near me that I can trust. I want to learn but never have had the chance. Sorry just ranting

What did they do to the 4x4. Any way they could have pinched a line while performing repairs. Also if it’s rich coming out of tail pipe then could be a faulty o2 sensor or injector since you said it has a misfire.

 

[Jeepmedic46]

They installed a Azzys design linkage since the old linkage had fallen apart and the Jeep is so old they couldn’t find new linkage for it.

 

[Jeepmedic46]

What did they do to the 4x4. Any way they could have pinched a line while performing repairs. Also if it’s rich coming out of tail pipe then could be a faulty o2 sensor or injector since you said it has a misfire.

If it was a o2 sensor or a injector wouldn’t the check engine light come on?

 

[M Rose]

Injector seals won’t throw a code, and the 4.0L is notorious for injector rail leaks, hence they make a kit to replace the fuel rail connectors and injector o rings...

Leaky Fuel Line to Fuel Rail Replacement/Fix - Jeep Cherokee Forum

XJ Cherokee Write-Ups - Leaky Fuel Line to Fuel Rail Replacement/Fix - If your XJ is leaking fuel and you have pin pointed the spot as coming from the fuel line that runs to the fuel rail then this will solve that problem. The main reason this happens is because the metal bracket holding the...

www.cherokeeforum.com

Fuel Injector O-Rings - Fuel Injector O Ring Kits

We have the best Fuel Injector O-Ring for the right price. Buy online for free next day delivery or same day pickup at a store near you.

www.autozone.com

looks like the kit is no longer available at the aftermarket level.IIRC the last one I installed I had to order from Chrysler.

 

[Jeepmedic46]

Injector seals won’t throw a code, and the 4.0L is notorious for injector rail leaks, hence they make a kit to replace the fuel rail connectors and injector o rings...

Leaky Fuel Line to Fuel Rail Replacement/Fix - Jeep Cherokee Forum

XJ Cherokee Write-Ups - Leaky Fuel Line to Fuel Rail Replacement/Fix - If your XJ is leaking fuel and you have pin pointed the spot as coming from the fuel line that runs to the fuel rail then this will solve that problem. The main reason this happens is because the metal bracket holding the...

www.cherokeeforum.com

Fuel Injector O-Rings - Fuel Injector O Ring Kits

We have the best Fuel Injector O-Ring for the right price. Buy online for free next day delivery or same day pickup at a store near you.

www.autozone.com

looks like the kit is no longer available at the aftermarket level.IIRC the last one I installed I had to order from Chrysler.

If this is the problem can the vehicle be driven? I only drive it locally. I have to wait till I get my next disability check.

 

[Boostpowered]

Pesonally if i were smelling gas as described. i wouldnt drive it until i figured out whats up. Might just have to put the ole sniffer to work and start smelling every part that deals with gas until you locate it.

If you absolutely must drive it carry a fire extinguisher or two

 

[M Rose]

^^what boosted said^^

 

[Jeepmedic46]

If I change the injector seals do I change the injectors as well.

 

[M Rose]

If I change the injector seals do I change the injectors as well.

No, just the seals and o rings, and possibly the fuel line to fuel rail connector. Its a very easy job to do, minimal tools required, and zero knowledge of how to do it. If you do get stuck trying to figure out how to replace the o rings and or connector, just YouTube it.

 

[Jeepmedic46]

No, just the seals and o rings, and possibly the fuel line to fuel rail connector. Its a very easy job to do, minimal tools required, and zero knowledge of how to do it. If you do get stuck trying to figure out how to replace the o rings and or connector, just YouTube it.

I did look on you tube and it showed me how to replace the injectors. Couldn’t find how to replace seals.

 

[SinisterJK]

I know it may sound crazy but check your charcoal/ Evap canister. Sometimes when your wheeling even in lite situations because they are located relatively low in the frame you can crack or damage them and it could cause the smell of fuel. I would also check the Injector Seals & Fuel Rail seals as well those are the first ones which are under pressure along with fuel filter connections. If all of that pans out then look into the exhaust. Not sure if your In a snowy climate and the salt on the roads could eat away your piping over 19 years of use on her. Definitely want to check every angle the last thing you want is to be another statistic with the jeep lit like a Christmas tree on the side of the road either. Im a tech id be more than happy to help you out even if remotely or via FACETIME and go over the jeep with you to help you diag the fuel smell issue.

 

[SinisterJK]

I did look on you tube and it showed me how to replace the injectors. Couldn’t find how to replace seals.

seals are easy but you need an O ring pick set. You can get one at the autocrats when you pick up your seals they're relatively cheap and will work down the line for a bajillion little projects or situations when you may need a tiny poker of some sort.

 

[M Rose]

I did look on you tube and it showed me how to replace the injectors. Couldn’t find how to replace seals.

It’s the same process to replace the fuel injectors, just remove the o rings and put new ones on instead of putting in new fuel injectors.

 

[Josh56]

If it was a o2 sensor or a injector wouldn’t the check engine light come on?

Injector can but biased lean o2 usually doesn’t. It sees its lean and computer makes up for it by dumping fuel. Check to exterior leaks first. Then internal leaks. Injectors. Then look at o2. If you have a scanner data can confirm a biased o2 fairly quickly.
Josh