need mechanical help

[Supertom1969]

I have a 1990 T4R I bought from a friend that was running but running like crap. Turned out the engine only had about 25 lbs. of compression. So, I put a new long block in it. ie: Block, crank, pistons, heads, cams, etc. Once I got it back together it cranked and ran fine. Drove it home from where I was working on it. about a week later I drove it to work and all was good. I left work that evening and on the way home I stopped at a stop sign and started to take off but it would die everytime I pushed the gas. and it continues to do it now. It is only the ffirst touch of the gas, once I push it harder it will stay running, but if you try to take off normally it will die. It is also running a little rich. I don't know what the problem could be. I assume it has to be fuel and air but don't know where to start to look.

Thanks for any and all help.

Tommy B.

 

[xUSNavy]

Start with the basics i.e. spark, air, fuel. I would start by pulling each spark plug and check for spark.

How is it idling? is it rough? smooth?

 

[shootmymime]

is there smoke? corect me if im wrong but it was running with alot of gas in the engine it would smoke?

could it be the mass air flow sensor? (its on the intake)

 

[RamThis]

Have you replaced your O2 sensors lately??

Not sure if 90 model 4Runners are OBDI or not, but if it is maybe you can pull some basic codes? I know OBDII came out in 96 so it's not as easy to troubleshoot earlier model years through the engine's control module.

 

[Supertom1969]

There is smoke, and you can smell fuel in the exhaust. It is idleing fine. Well, I say it is. It idles fine for a while but the longer it runs the worse it will idle. I just hate knowing that I spent about $2400 time and labor on putting a new engine in it and can't drive it because of something that is propably simple.

 

[RamThis]

If you have not changed the O2 sensors, I'd start there. Even if they dont end up being the problem, they need to be changed every 50-75K anyway. Just changed them on my 2000 Ram at about 70K, mileage was getting worse, and worse, and worse, then it started idling rough and would belch out alot of smoke when I stomped on the throttle, till finally it threw a CEL code, looked up the code and it was the O2 sensor, exactly what I suspected was going out when the mileage started dropping and the black fuel smoke belched out when I stomped on it.