Running Rich on the Right

[yakumo2897]

Hello everyone,

I just bought a 300zx twin turbo that was swaped. This car has a myrid of problems but the most notable is a hesitation if it is in gear at idle and it running rich. You can smell gas from the drivers side.

Everything I have read states that this can be
Passengers 02 sensor
Bad Cat (God I hope Not)
non NGK spark plugs
or the fuel filter being bad. Seeing as this engine has 54k, any ideas on what else might be wrong

I know its the right side becuase black stuff is coming out only on the right tail pipe, both sides smell rich though.

No smoke and the car pulls hard.

Thanks in advance.

Robert

[confused9]

Do you have plans to do any of those? I was going to suggest fuel filter.

[yakumo2897]

I already ordered the fuel filter it will be here in a couple days I will keep you posted. I plan on doing all of it but am limited on funds right now.

[evildky]

Scratch "non NGK plugs" off your list, could be bad plug(s) it's not the brand that makes the difference. I like Denso, NGK or Bosch are my fall backs. Step one should be to check the ecu for codes. step 2 should be to pull the plugs and have a look at them, might be able to find the bad cylinder by the look of the plug and at that it could be a bad plug, COP or other ignition problem but locating the issue is a necessary step is fixing it. It could be the cats, lots of people gutted their stock cats to gain that uber JDM powar! Also you said at idle in gear so it' got an auto?

Also do you know that the eigne had 54k miles? did the swap come from a front cut with the odometer? if not it's mileage unknown, I've seen "low miles JDM" engines with oversized bearings, so unless you have proof of the milage lets assume it's closer to 200k miles. Then lets remember it was haphazardly shoved in a container with as many other engines as they could fit, this one might have been on top of the pile, or the bottom, then it spent a month on a slow boat from china (er japan) being bathed in salty ocean air, to then get trucked across the country in that same container before being unloaded and untangled from it's shipping mates, and stuffed on a shelf in a warehouse somewhere and sat for who knows how long before you got it. If indeed it was part of a front cut you can assume it was on the bottom of the pile but at least it had portions of a unibody insulating it from the others around it.

[yakumo2897]

The swap did come with the odometer, It was an entire front clip so I am not so worried about that. I guess checking the ecu is the next step. It is a manual but there is a hesitation if I am at a stop put it into first and step on it. Almost like a delay for the car to actually realize that I need it move. After though it runs and shifts through all the gears with no smoke or back fire you wouldn't know anything was wrong if you didn't stop.

[confused9]

Now that you a good bit of info let us know when you've crossed some troubleshooting steps off!

[evildky]

I cant help but wonder if what you are feeling is bad motor mounts? These were liquid filled on the Z32 (Nissan was an early adopter of this now prevalent, terrible technology that basically guarantees the part will have a finite life then self destruct).

[yakumo2897]

Ill add it to the list but I really hope not the engine bay in this car is tiny.

[evildky]

Hint. you access the mounts from the bottom, and it's still a PITA! Engine bay isn't tiny, engine is large with loads of extra bits stuck on clogging things up, it's engineering for engineering's sake.

[yakumo2897]

Ended up being a missing egr valve. When they did the swap they never put it, also one of the cats was gutted on one side. Sorry for the tread resurrection, but I love my Z