Gas smell in cabin after turning on heater - help!

jet911 · 06:15 AM

Looking for a bit of help - '86 Carrera coupe.

Did a search but didn't get much.

This morning I turned on the heater for the first time this season and got a blast of gas fumes. The smell seemed to subside after the fan blew for a couple of minutes. When I got to work I opened the engine compartment trying to see if I could locate where the smell was coming from. I thought I smelled a very faint gas oder on the driver side of the engine, however it was nothing like what came from the heater's initial blast, and no smell on the passenger side. I felt around the fuel filter connections and they were dry.

I changed out the plugs two weeks ago and there was no gas oder nor were there any damp/wet places on the drives side that I noticed, however there was one small spot on the valve cover above the # 6 plug hole on the passengers side of some sort of residue, did not smell. I have not noticed any smell prior or any spots on the floor indicating a leak.

I was going to do my long awaited first valve adjustment this Friday, so I'll have everything out on both sides of the engine.

Where should I be looking to see where the leak may be coming from?

TIA

JeremyD · JeremyD's Garage

Check the fuel line - do a search on carrera fuel line and carry a fire extinguisher with you until you find the leak. better yet - find the leak before you drive.

jet911 · 09-13-2005, 12:21 PM

Jeremy - Thanks
Did a search for Carrera fuel Line and found a ton of threads!

jet911 · 09-13-2005, 05:23 PM

Okay,
Got home tonight and spent a good half hour going over every fuel line connection in the engine bay. Not one leak of any kind anywhere. All lines looked good, nearly like new. No gas fumes and when I ran the heater, no smell. I then went to the luggage compartment and checked around the gas tank, the filler hose. No smell, no leaking. I'm sort of stumped. I'll let the car cool down, start her up again, turn of the heater and see what happens.

Any other ideas?

kqw · 09-13-2005, 07:01 PM

Same thing happened to me several years ago.

In the morning when I started up the car and turned on the heater, I would get a wiff of gas smell. A few miles of driving and it would go away.

Turned out to be the center fuel line. Hard to diagnose as I LOOKED everywhere. The problem is that gas is going to evaporate because of heat, therefore it left no visible trace.

Finally went to the dealer where I bought the car and they immediately knew what the problem was.

Eric Coffey · 09-13-2005, 09:54 PM

If it's a center (tunnel) line leak, there will usually be a visible fuel "residue" trail. If it's the notoriously leak-prone fuel rail/damper/regulator connecter line, it can be harder to tell. That line will typically form pinhole leaks that are only detectable when the engine is running. Even then, you might have to remove the heater blower assembly and/or intake/airbox to pinpoint the leak (with a good light source and inspection mirror).

jet911 · 09-14-2005, 05:29 AM

Thanks for the ideas guys. This morning on the way to work, ran the heater - no smell at all. Tomorrow when I take the heater blower assembly out and the air box and AC compressor to tackle the valve adjust, I will take a very close look at the connector line.

kqw · 09-14-2005, 05:48 AM

Good deal...

However: You know what you smelled earlier, you know the smell of gas and you know there's an issue.

In my experience, there is no such thing as "an occasional" smell of gas. That kind of issue does not just go away...

Find the problem quickly....

Cheers.

JeremyD · JeremyD's Garage

and if you contine to drive it - carry a fire extinguisher. A big one.

jet911 · 06:21 AM

Thanks for the responses and concern. She will be parked tomorrow and I will start dismantling the engine compartment in preperation for the valve adjustment. I will have access to the back of the engine and be able to check in more detail. I'm not going to forget it because it seems to have gone away, I will find out what/where is going on. To dangerous not too.
Thanks again.

brcorp · brcorp's Garage

Don't turn the heat on.

Sorry, had to be a smart ass

jet911 · 09-14-2005, 06:34 AM

I did speak with another P-car owner who experiences the same thing every year he turns on the heater after it has sat for 6 - 8 months. He told me that it smells similar to gas, but it is not. He told me it is simply residue that has built up over the spring/summer season and burns off after running the heater on high for 4 - 5 minutes. Don't know for sure. I guess the other thing that is interesting is last night I ran the motor letting her get up to operating temp., with the engine compartment open and fire extinguisher in hand, stuck my nose all over the engine bay - no gas smell at all. Used a flashlight to check every fuel line connection and saw no sign what-so-ever of a leak. Turned the car off went out to the garage this morning, so gas smell at all (there has never been a gas smell) and she has the garage to herself. I would think if there was a leak I would smell it every morning. Not trying to talk myself out of a possible issue, just stating what has been happening. I'm just a bit frustrated and looking at all possible explainations. I will definitally check all hoses and connections again starting tomorrow.

Thanks again.

kqw · 07:04 AM

Quote:

Originally posted by jet911
I did speak with another P-car owner who experiences the same thing every year he turns on the heater after it has sat for 6 - 8 months. He told me that it smells similar to gas, but it is not. He told me it is simply residue that has built up over the spring/summer season and burns off after running the heater on high for 4 - 5 minutes. Don't know for sure. Thanks again.

OoooKay!!!

Just for reference, here's info that solved my issue:

Service ticket that was written up said:

"Customer states smell of fuel upon start up and turning on heat"

Diagnosis from Technician: "Leaks at area of #1 Intake runner and drips gas into heater duct"

Work performed:

Replace Center fuel line - Part# - P93011059505 - qty. 1

Replace Intake Distr. Gask. Part# - P93011019711 - qty 12

Just for reference.....of course....

jet911 · 09:45 AM

Thanks kqw.

I did check last night the center fuel line at the T, the connection at the fuel filter, the connection from the rubber to solid line and at both connections to the rails/runners, particularly the one on the drivers side where the heater duct is. No leaks. I will check more closely tomorrow after I remove heat duct.

The difference is that my car does not smell on start-up nor any other time, except this one time when I turned on the heat for the first time in 6 months.

kqw · 09-14-2005, 08:17 AM

Very good....

Thanks,

ryanmt · 09-14-2005, 08:48 AM

I found the fuel smell in my car to be coming from the fuel tank overflow lines leaking in the trunk. I replaced that line and haven't had anymore cabin fuel smells.

rick-l · 09-14-2005, 11:40 AM

So I have some incentive to keep going and not feel totally stupid, what did this cost you?

The gaskets between the insulator and the cylinder head on the intake manifold just laugh at me, the permatex gasket remover and a putty knife. I have spent two hours on this so far with my head jammed in there and am not completely done. How does a mechanic do this and get paid for it?

After the engine is hot, shut it off and immediately put your hand down around the two (rear of engine) rubber parts of the $360 fuel line and see if they are wet with gas. It evaporates pretty fast. The rubber pieces of the expensive line that rot and crack are at the back of the engine (i thought that would be #3)

Quote:

Originally posted by kqw
OoooKay!!!

Just for reference, here's info that solved my issue:

Service ticket that was written up said:

"Customer states smell of fuel upon start up and turning on heat"

Diagnosis from Technician: "Leaks at area of #1 Intake runner and drips gas into heater duct"

Work performed:

Replace Center fuel line - Part# - P93011059505 - qty. 1

Replace Intake Distr. Gask. Part# - P93011019711 - qty 12

Just for reference.....of course....

kqw · 09-14-2005, 03:42 PM

The total cost to me was $233.00...Caveat...the dealer picked up the cost of labor. Labor hours on the ticket indicated 4.5 hours.

Looks like you are attacking it the right way...

As you know, if fuel hits the wrong place at the wrong time, or that line gives away (pressure) oh boy.....

Hang in there.

jet911 · 09-15-2005, 09:46 AM

Not a bad deal at all Fox. Part 93011059505 sells here at PP for $361 and 93011019711 are cheap $1.37. Your wrench did you right! Nice to hear.

Take care!