Exhaust smells of raw fuel/poor mileage
 

I haven't been able to find problems similar to mine so I thought I'd make a new thread.

I have a 1996 Maxima, automatic, 231k miles. My exhaust smells a lot like raw gasoline and I feel like I'm getting poor gas mileage too. It smells more so than any other cars I'm around, even the older ones like mine. I can't smell gas at all on my brothers 1997 explorer. I recently changed an O2 sensor, knock sensor, fuel filter and fixed up the EVAP system (which was a pita). That got rid of all codes and I passed smog. My intake was cracked and janky in general so I replaced it with a short intake. It kept all the old sensors so I don't think it's hurting to much if at all. I figure it has to be better than the leaky one. To add some more Info, I originally had to fail a smog for dmv purposes and the emissions numbers were really low and looked good. But I had codes so I didn't pass. Then once I actually passed(after fixing evap issue) the numbers were a lot higher and it barely passed. At the moment I have no codes and the car feels like it's running great, beside the smell and mileage.

Help would be greatly appreciated!

Our cars sometimes run super rich because the fuel injectors can develop leaks. This issue can also cause difficult starting.

Please elaborate about the intake. What does cracked and janky mean? Is this an aftermarket setup?

Are there any leaks in the system between the maf and the throttle body?

I have no issues starting. I also got my oil tested and there was no gasoline found in the oil. Yes I have an aftermarket setup now. The original one had cracks in it and things were loose and what not, held together with zip ties. So I decided to replace it, there are no leaks between the MAF and tb now.

I have considered changing the injectors anyway becuse my fuel filter was never changed over the course of 227k miles. When I pulled it black fuel came out both ends, even after passing though the filter. I figure they may have been damaged

Check your fuel lines. If your smelling fuel in the cabin it could be a line leading to the fuel rail. I had a fuel smell coming through the air vents and it was because of a hose that was leaking. When the engine warmed up and the hose expanded, the smell would dissipate but remain faint in the cabin. Don't have a picture of the hose but if there is a leak there will be residual dirt/fuel on the hose, I just rubbed my finger around fuel hoses to find the leak.

I'm only smelling it from the ehasut really. If I go smell right at the tail pipe. I can smell exhaust under the hood on the driver side near the fire wall only which makes me think there's a leak there, if there is it's really small. I've looked into replacing the headers and it looks like a job and a half.


Maybe I'll inspect my injectors and fuel rail today. There are no visible leaks though but who knows, maybe I'll find something

https://cimg8.ibsrv.net/gimg/maxima....4f16ee5f9.jpeg
So I just pulled 2 injectors to look at them. They were a little dirty and one even had a crack on the small plastic tip. Here's some pictures.
https://cimg4.ibsrv.net/gimg/maxima....5e909ca270.jpg

https://cimg5.ibsrv.net/gimg/maxima....99b4cfb859.jpg

Injector refurb is well in order.

No arguments or rationalizations ... rebuilding your injectors is what's needed.

Plain ... simple.

I would agree... Hopefully it solves my issue. New ones are quite pricy for me, so how much would a refurb run?

rebuilding is about $20 a piece i believe, around 120$-150$ for all 6 from what I heard, best to do all 6 while your at it. do not do one.. cause the other worn out ones will come along as well.

To say you couldn't find a thread with a similar problem to yours is :jeffy:

By your thread title alone, it's a dead giveaway it's your injector(s).

Have a fuel injector service company professionally clean them internally and rebuild them with new parts (o-rings, pintle caps etc). About $120 as stated already. If you can't have your car down for two weeks waiting for this service, then buy rebuilt/cleaned injectors on Ebay for about the same.

http://www.ebay.com/itm/Jecs-Flow-Ma...BSp1Y4&vxp=mtr

New ones for $60? hmmmm.....
http://www.ebay.com/itm/6Pcs-OEM-Fue...RWePKU&vxp=mtr

Thanks for the fast replys! The reassurance is nice to have. I'm leaning toward new ones because it would be nearly impossible for me to have my car down for 2 weeks.

Wow there's a lot of low priced sets on eBay. It sure beats the $210 I found them for elsewhere.

I had mine done by Injector RX in houston. Very quick turn around time.

You will need to remove the uim to get at the back ones.

Please replace all fuel hoses when you are in there. Gas filter too if it had not been replaced since you bought the car.

The egr tube is accessible then as well. Might consider cleaning it.

Also the heater hoses. Easy to replace while uim is off, not so much when it is on. Better safe than sorry.

Yeah I was planning on doing valve cover gaskets as well.

I live in Houston and called InjectorRX about servicing mine. They described a price $5 higher per injector for "walk in" (while you wait) service. Perhaps coordinating fast shipping and expedited service could cut that 2 weeks down to five days or similar.

Five days was my turn around time from them. In in Oregon.