Strong exhaust smell on 87' with TBI

[92470]

I know this is a real open ended question, but I have a 87' V10 w/5.7 that always has a very strong exhaust smell that I want to get rid of. My garage, clothes, hair, smell after I drive it and the wife is sick of it. Motor has never been rebuilt and is stock with 145,000 miles. Exhaust is dual with no cat. Truck always starts and runs fine. Sometimes dies when is started and put into reverse. This is only in reverse (strange). When I start it, white exhaust comes out of both pipes and smells very strong (not a oil smell, but more like fuel). Goes away after start up, but still has strong exhaust smell. If you barely give it fuel, it sputters, but doesn't die. Those are the facts.

I checked the TBI and spray looks good with timing light, and there is no fuel drip or pooling after shut off. I just adjusted timing , and noticed no real differance. All vaccum lines look good, and I see no leaks. EGR also operates as it should. Coolant temp switch is new. What else should I check out? I don't want to throw parts at it, but wondering if anything else stands out to you guys given the facts here. I know older vehicles exhaust smell stronger and with no cat, could be the case, but smell has got to go. Any direction is appreciated. Thanks

[Matt Man]

where does your exhaust end? thats pretty bad if you smell like it not healthy. Also does it have cats in it?

[92470]

Exhaust ends at rear under bumper and no cats.

[clinebarger]

Originally Posted by 92470

I know this is a real open ended question, but I have a 87' V10 w/5.7 that always has a very strong exhaust smell that I want to get rid of. My garage, clothes, hair, smell after I drive it and the wife is sick of it. Motor has never been rebuilt and is stock with 145,000 miles. Exhaust is dual with no cat. Truck always starts and runs fine. Sometimes dies when is started and put into reverse. This is only in reverse (strange). When I start it, white exhaust comes out of both pipes and smells very strong (not a oil smell, but more like fuel). Goes away after start up, but still has strong exhaust smell. If you barely give it fuel, it sputters, but doesn't die. Those are the facts.

I checked the TBI and spray looks good with timing light, and there is no fuel drip or pooling after shut off. I just adjusted timing , and noticed no real differance. All vaccum lines look good, and I see no leaks. EGR also operates as it should. Coolant temp switch is new. What else should I check out? I don't want to throw parts at it, but wondering if anything else stands out to you guys given the facts here. I know older vehicles exhaust smell stronger and with no cat, could be the case, but smell has got to go. Any direction is appreciated. Thanks

Check the vacuum line going to the MAP sensor. Without vacuum to the MAP sensor the computer will overfuel the engine. Also check fuel pressure (9-13 psi). Leaking fuel pressure regulator. & leaking injector(s) can also cause this

[shloopter]

Ditto what Clinebarger said. Vacuum to the MAP sensor came off on ours and it ran bad at startup with smoke and a little studder then ran great after that. We smelled like gas when we got out of the truck. Gas smell can also be a cracked gas line under the hood.

White smoke on startup can also be valve guide seals. These can be replaced without taking the heads off. Talk to your mechanic.

Good Luck

[92470]

I've checked the line going to the MAP sensor and it looked solid, but I have a length of tube that I can replace it with and see if it makes a difference. I know the factory line is kind of a molded tube at a angle. If I just use a flexible piece of standard vaccum line I think this would be suitable for a trial anyway. If the MAP sensor was bad, would it throw a trouble code and turn the check engine light on for sure? I guess I am wondering if the MAP sensor could be going bad and my check engine light isn't coming on.

[shloopter]

MAP sensor could be going bad also. As soon as you lose vacuum the Check Engine light should light up. Mine went on as soon as I started it after forgetting to hook up the hose. Check the boots that the hose plugs into as well.