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-   -   fuel smell (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/fuel-smell-935447/)

ericgrau 12-23-10 09:05 PM

fuel smell
 
I need help finding where a fuel smell is coming from. It comes and goes... I think, or maybe I'm just used to it. Sometimes my eyes even sting. Already replaced the fuel pulsation dampener 40k ago and it doesn't seem to be leaking, but I'm gonna check again. Replaced a cat that supposedly had a hole in it, or maybe the exhaust shop was trying to rob me. Car passes smog. Where else should I check?

A/C has been leaking repeatedly, but I think the last hole of many was finally dealt with. I hope. Dunno if freon would smell the same.

thejallenator 12-23-10 09:10 PM

i was under the impression all rx7s smelled of gas......

misterstyx69 12-23-10 09:10 PM

You can always Jump the Fuel connector and see if the System is leaking at or on the engine.
Key on..jump connector with a paper clip..it will Power the pump and create pressure so you can see if there are any leaks.

3vil 12-24-10 12:24 AM

check inside the car in back. pull back the carpet and see if you can smell the fuel more near the two access hatches.

Bamato 12-24-10 02:15 PM

Check around the fuel injectors as well. Its common for injectors to leak from the clips when they are older...

jjcobm 12-24-10 02:59 PM

Pressurize the fuel system via the yellow jumper. Let it run for 30min while you search for leaks. Obviously you will have to possibly pull off the upper intake manifold. Under no circumstance should you keep driving the car if the fuel smell is strong. If you didn't pressurize your fuel system before buttoning the fuel lines back up after your 40k pulsation dampner replacement, then its quite possible one of your fuel lines are leaking due to not being connected properly.

Check all your fuel lines from the fuel tank up to the fuel rails. (While system is pressurized)

Next, you are in california, so I am assuming you have the emissions systems still. Check the connections for the charcoal canister, if it's improperly connected, you will get fuel vapor smell in the engine bay.

Finally, if you are 100% sure there are no fuel leaks, the next step is to make sure your weather seals are in tact. If you have a coupe, the rear hatch seal can let fumes into the car if its bad. But I wouldn't do this step until you have verified everything else.

ericgrau 12-25-10 10:04 AM

Where's the yellow jumper? Or will it be easy to find in the fuel system section of the FSM?

I'm not sure but I think the smell is somewhere in the engine bay.

wjk0817 12-25-10 03:30 PM

dunno much, but judging by my rx7, fuel smell and rx7 are complimentary. im used to it

3vil 12-25-10 03:40 PM

the yellow jumper (fuel check connector) is right by the AFM, on the passenger side in front of the shock tower.

jackhild59 12-25-10 04:30 PM

Does the smell correspond with the gas tank level? I am JUST RIGHT NOW finishing up replacing a gas tank that has rusted. In addition to the tank rust, the fuel vapor return to the gas tank filler was also rusted off. We got gas smell only if the tank was over half full.

This was a pretty dangerous situation.

I have replaced everything from the fuel filler to the fuel lines. The inside of the tank was amazingly clean and rust free, but the outside was frightening.


This was a canadian GXL that some how found it's way to Texas. I have learned there is no such thing as a cheap Rx7...

thejallenator 12-25-10 05:28 PM


Originally Posted by jackhild59 (Post 10383699)
. I have learned there is no such thing as a cheap Rx7...

that should be the first thing any rx7 owner should learn. hands down. then would be the search function on this site.

ericgrau 12-25-10 06:39 PM

I'm probably imagining it but I think the smell is worse when my fuel is low. Thanks for pointing out the jumper I'll do an inspection as soon as I get some free time. In the mean time I'm going to make sure it's not the pulsation dampener. Are there any other places where a leak would be dangerous? The smell is bearable for me at least b/c I'm used to it; enough to forget it's there. Sounds like many others ignore it haha.

jjcobm 12-25-10 11:45 PM


Originally Posted by ericgrau (Post 10383808)
Are there any other places where a leak would be dangerous? The smell is bearable for me at least b/c I'm used to it; enough to forget it's there. Sounds like many others ignore it haha.

Ummm.... I don't know about your world, but typically having fuel leaking anywhere is usually a sign things are going to burst into flames soon.

Bamato 12-26-10 04:10 PM

Fuel leaks aren't something to be shrugged off for later...

Cratecruncher 12-26-10 06:03 PM

There are many opportunities for fuel leaks under the hood, around the emissions components, fuel injector- to-rail seals (primaries are hard to see). I was recently bringing my '87 out of hibernation and found the fuel pump was frozen up. While fishing the pump out of the tank I decided to also replace the fuel line hoses on top of the tank. They were the originals - even had a 1986 date printed on the hoses! (If the smell is strong inside the car at speed it might be coming from this area.)

When looking for a fuel leak there are some tell-tales I look for. When fuel evaporates the most volatile components escape leaving behind an oily residue with an orange tinge that attracts dirt similar to an oil leak but not as obvious. Try to be thorough and systematic. Follow the lines from A to Z and back to A and you should find an obvious leak. If the vapors are stinging your eyes that's a LOT of gasoline. Good luck.

driftxsequence 12-26-10 08:21 PM

i had a fuel smell, and i couldnt pass the emissions for inspection. I replaced the soft lines from the fuel pump but still failed. It turned out to be the small soft line near fuel neck. After i replaced that, it pressurized properly and when taking of the gas cap, it had a suction noise.

ericgrau 12-28-10 11:21 AM

It's usually not that bad of a smell and if I feel it in my eyes it's barely but ya I'll check it out. Dang it I have no free time lately to do this kind of thing. Too many other crazy things to take care of. Checked the paper towel under the fuel pulsation dampener this morning and it came out dry.

Bamato 12-28-10 11:25 AM

You'll have lots of other stuff to do (ie burn wound dressing re-applications, insurance claims, etc) when your car starts fire... ;)

Can you avoid driving it for a short while till you can find the time to locate your source of the fuel vapor?

ericgrau 12-28-10 11:59 AM

Well the smell has been there for a while. How much would a mechanic charge to inspect the fuel lines? I got a billion things to handle this week before new years that should have been done last week.

staticguitar313 12-28-10 12:03 PM

Wouldn't take much cost wise or time wise to go and change your fuel lines to be safe. Do that, the PD eliminator mod and change your injector O-rings, also inspect your charcoal canister and the lines running to it. All cheap to do. while you have the manifold off you can do an emission simplification if you haven't and replace the coolant hoses.

Cratecruncher 12-28-10 12:42 PM


Originally Posted by ericgrau (Post 10387016)
How much would a mechanic charge to inspect the fuel lines?

Wow, thats a tough one. The going rate around here is $50-100 per hour. Independents are on the lower end, dealers at the top. Watch out because if you bring a car with an unknown problem to diagnose to a shop you don't know, your vulnerable. The guy can burn through your money "hunting" until you give up and ask for your car back - and the problem is still unknown. Until you find it there is no finite solution to the problem. Best to figure it out, then hire a mech.

durtled 12-28-10 12:52 PM

maybe ur gas tank has a hole in it towards the top? i know mine does 1 of the things im replacing this winter.

ericgrau 12-28-10 01:52 PM


Originally Posted by Cratecruncher (Post 10387086)
Wow, thats a tough one. The going rate around here is $50-100 per hour. Independents are on the lower end, dealers at the top. Watch out because if you bring a car with an unknown problem to diagnose to a shop you don't know, your vulnerable. The guy can burn through your money "hunting" until you give up and ask for your car back - and the problem is still unknown. Until you find it there is no finite solution to the problem. Best to figure it out, then hire a mech.

Let's say I know a good one, or at the very least ask him to inspect X Y Z and show me any supposed issues. How many hours? I mean I'd think once it's on a lift it might be an 1/2 hour to hour inspection, I hope. Jack and jack stands with dirty hard to reach surfaces are more trouble.


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