Fumes in cockpit

[fae821w]

My 280zx went into the local garage today for its MOT, it passed easily with no problems, with only lots of comments on how good the car is. However i had also asked them to see if they could find the source of fumes, engine or exhaust, entering into the cockpit.

When driven, i have these fumes which are more apparent when a window is open. I suspected leaks from the manifold or exhaust, there are none. I have changed the boot seal to a bigger type and adjusted the tailgate to fit better, but no real improvement. I have checked the rear light seals, again not these.

The garage say the emissions are good and the car is not running rich and are unable to find a cause.

I have seen a thread at sometime when this problem was mentioned, but with no conclusion. Can anyone advise please.

Thanks,

Andy.

PS, Thanks again to Candyred (Derrick) for his help on tracking down a sidelights fault.

 

[candy red]

Hi Andy you need to check the fire wall for any holes might just be screw holes that are no longer used small grommets will solve this also check all rubber seals around heater pipes around cables,check everywhere where something goes through the firewall into the cockpit
also check the seal between the gear lever gaitor and the tunnell.A holes no matter how small will let fumes in hope this might help good luck

Derrick

 

[cosworth415]

Just got a gear stick to tunnel rubber gaiter turned up yesterday from Tokyo, all in all set me back £60 but it is a genuine Nissan part.

 

[SeanDezart]

Exhaust fumes come from....the rear of the exhaust !

 

[johnymd]

A very common problem on zeds and its nearly always due to the vacuum created in the cabin when the window is opened. exhaust fumes are sucked in from the back of the car. Usually a perished grommet or poor seat around a fuel hose that enters the cabin. The other main culprits, which you have already done, are rear light seals and tailgate seal/grommets.

 

[Huw]

Hi Andy

Couple of other places to check, the gearshift tunnel boot (that was the cause for me) as these split. Tail light gaskets, these degrade with age and can allow exhaust gassed to be drawn back into the cabin.

Huw

 

[monza]

Lots of good advice given, I had a similar problem years ago and now agree with the theory that the fumes can be drawn from the back of the car and roll along the bodywork to get into the cockpit....on that occasion i had to replace the sunroof seal to eliminate the problem...i sh1t you not ( i took the seal off again to prove to myself that i wasn't going bonkers, and the problem returned ).

I've also had to lay in the boot area with a feeler guage to insert between rear hatch and the rubber hatch seal...its the only way to ensure that you have a good seal ( i didnt ).

Masking tape is a good quick way of proving problems on the back end - mask off the gap between the rear hatch and body ( make sure you get a good seal or you will waste your time ), you can get the tape in varying widths - i get the two inch wide stuff as it easily bridges panel gaps.

Check the fuel pump 'access' cover in the boot area is still in place and sealed, you may even have to look for rust holes / poor repairs ( incomplete seams of weld ) in the rear valance and rear arches and around the tank filler pipework - best to strip the boot trim out and mask off with paper all the holes in the back end to try to an narrow down problem.

And....you might even need to check that the scuttle vent ( between the wipers ) is clear and allowing air into the car...on an old jag the vent was slightly clogged and the car was drawing air into the cabin by the scuttle drains in the bulkhead, some off which went into the engine bay...obvious really when the problem was solved but not the first place anyone would look !.

 

[niroshann]

I could never figure this one out in my old ZX. Doesn't happen in the one I have now. I recall turning up the blower fan in the cabin to try "push" the fumes away!!

 

[Rob Gaskin]

I could never figure this one out in my old ZX. Doesn't happen in the one I have now. I recall turning up the blower fan in the cabin to try "push" the fumes away!!

Yeh, I used to close the windows and have the fan on in my old 240Z. Positive pressure did the trick.

 

[fae821w]

Many thanks everyone for the replies, very helpful, i will check all these areas.

I have just returned from Northern Spain, saw an orange 240z in Plymouth on Sunday 29th May, was this a Members, maybe Nmd14 Nick D?

Cheers,

Andy.