Fumes in the cockpit (DHC) while driving.

[Keith Scarfe]

Is it common? Does anyone else suffer from smelling exhaust type fumes while driving or is it just me?
I say 'type' fumes because I wonder if it might be fumes from the engine bay (leaking oil fumes) coming in somewhere, but I am pretty sure it is exhaust fumes. I tried sealing up the fresh(?) air intake to see if it was fumes from the engine bay coming out of the bonnet gap and going straight into the intake plenum but I think I proved it wasn't this. My car does burn rather a lot of oil and smokes like a chimney out of the tail pipe so I think this is why it may smell worse than normal but I was wondering if anyone else suffers with this when topless. The exhaust doesn't leak anywhere like at the manifold so it must be exiting as normal and blowing back into the cockpit. I seem to remember it has always done this from since when I first had the car some 20 years ago. I am also pretty sure I get it with the roof up but not as bad. I vary rarely drive with the roof on so will have to try this again sometime to see.
Any one have any ideas? Yes new piston rings would be one but not yet, not till it starts fouling the plugs. Maybe it could be the seal on the boot lid but it does seem good, how can I test this?
Thanks for any chat.
Keith.

[elanfan1]

I'm far from being an expert on such matters (or any at all really) but I'm sure I've read on here that the car creates a low pressure point behind it whilst driving and that can be a contributor - it can't be the only thing or else we'd all get it. Might be worth checking your exhaust clears the rear bumper my the prescribed margin.

My other thought was could it be coming up via the gearstick?

Good Luck with tracing the issue.

[ricarbo]

I don't know if this will help at all as my car is a fixed head. I had a lot of problems with exhaust fumes and was able to prove that the problem was my new boot seal by sealing the boot lid to the body with duct tape. not very kind to the paint!
regards
Richard

[elanman999]

Keith,
My Elan was very bad when I bought it. I have improved it alot by:- Sealing up EVERY hole in the boot floor and around the diff mountings.
Also make sure there are no holes in the rear inner wheel arch by the seat belt mountings. As Elanfan says the exhaust pipe can also be a problem if it ends a bit short it causes fumes to enter the boot.
Cheers
John

[Keith Scarfe]

Mmmm. OK thanks. I'll try sealing up the boot and going for a run. I'll use masking tape rather than duct tape though as yes I would be worried about it damaging the paint.
Yes I recon it probably is negative pressure in the cockpit when at speed so yes I guess any fumes will be sucked in to the cockpit then exit out of the top.
Cheers.

[nomad]

I have not experienced the exhaust smell on an Elan.[Mines still in pieces] Have experienced it with other roadsters and would suggest angling the end of the exhaust pipe down sharply and cut at about 45 degree's parallel to the ground. That seems to help a lot.

Kurt
26/3754

[Spyder fan]

The boot/trunk seal is a very good place to start diagnosing the problem. My +2 used to have an unreliable catch which would allow the boot to open if you went over a big bump in the road, I always knew it had happened when I could smell exhaust in the cabin.
As mentioned, the airflow over the car creates positive and negative air pressure meaning that air will be sucked/blown into the boot area and then the cabin if the boot is not sealed.

[Keith Scarfe]

Went for a long drive over the weekend with the roof UP (and it wasn't raining !!! Sacrilege) (wife on board) and the smell is definitely greatly reduced to the point I would say it is gone, but maybe not quite - perhaps it is just the original smell lingering. Do you think this would mean it is not coming in through the boot but in through the open top. Maybe with the roof up you don't get the negative pressure in the cockpit sucking the fumes in, I don't know, but what was also interesting is that I had a weekend bag full of clothes etc and when we arrived, the bag and all the contents smelt of exhaust fumes. So this suggests that it is coming in through the boot. I have ordered a new seal from Sue Miller and will fit this to see if it helps - wont hurt anyway. Haven't got round to the masking tape test but may try this one day.

[Keith Scarfe]

Well I recon it is fixed now. Boot seal trim arrived from Sue last week so fitted it over the weekend and first test drive was today. I can still smell the smell slightly but is hugely reduced from what it was. The smell wafts in when stationary (pulling up to a junction) but goes when driving now whereas is was also terrible while driving.
The trim I had on there before was something I found from work (some electrical cabinet door seal IIRC) and the new one from Sue was much chunkier. Meant the boot lid now has to be pressed down while the latch is engaged but this means the (now) good seal.
If you have fumes in your cockpit - Even in a DHC with the roof down - Get a new boot seal. No more feeling sick when arriving at destination. Yipee. (I hope).
HTH someone.
Keith.

[Spyder fan]

Great news that it's fixed!

Isn't this a great place? Imagine the bill you would have got from a specialist if you had asked them to investigate and fix it for you.