90' 4runner hard to start when cold, acceleration is really slow
 

Just got this 90' toyota 4runner 4wd 3.0 automatic a week ago, it was good running for a couple days. Now I'm having trouble with it. It is having a hard time starting up when cold, before it start up quick and drove off quick aswell. Now when i get it started it's well below 800rpms when cold. When warm up its all good.

And another thing way driving it don't have power to go up hills and acceleration is really slow i mean slow too. Take o/d off still the same.

Now the motor got knocking sound and it does have oil too. But sound is not loud.

No smoke or no check engine light on

Please help

Compression and leak-down tests. Knocking is a bad sign, your valves are shimmed not adjustable like the four cylinder. You'll need to use a stethoscope to isolate the location of the noise to get an idea of what is going on.

Go thru the manual trouble shooting chart "incorrect first idle", and I don't recall exactly what the other one is "hard start" maybe.

Check your timing and pull your codes. Some codes don't cause check engine to stay on. Also, check vacuum lines for leaks.

Idle is good when warm up, just hard to keep alive when i get it started.

I'll try to check the timing,but how do i get the codes. My dad said it sound like it misfiring. We work on honda and ford, but is the first toyota we ever got. I heard a lot good thing about the 4runner so i got for cheap well not cheap 1800.00. And i like to see it running good.

I am having the same issue with the rough start up. Mine takes forever to start. From what I have heard, the 3.0 auto's are notorious for lacking power, have heard many people are dropping the 5-speed manuel in them and having success. My 3.0 w/ 5-speed pulls really well going up hills. Is it knocking, or is it pinging?

Those are effectivly the same things in modern nomenclature. You have to specify "rod knock", or every one just assumes its the methanol issue :D

Check your cold start injector and weight of your oil could cause a hard start and a knocking.

To heavy weight of an oil could cause the oil to not act as a bearing between the cranck and your rod and because it is so thick it could take a while for it to warm up and let everything run right.

Does your oil smell like fuel?
If so try replacing the cold start and see if that helps

Also check your vacuum lines

Codes are just a matter of jumpering between T-E in the diagnostic connector mounted to the side of the fuse box in the engine compartment turn the ignition to on and counting the MIL flashes. It's covered in the manual, it says you need an SST but any piece of wire or a paper clip will work.

This is also the same place you need to jumper to set the timing.

As mentioned dilluted oil is a bad thing, but by the time you can smell the fuel build up its way past time to change it.

Another thing to check is the "Idle air control valve"/IACV, if this is stuck closed or blocked/dirty it won't breath right.

There is a troubleshooting flow chart in the manual under the engine section, just go step by step thru the "Incorrect first idle" or other relevent sections.

FSM Link

Got a code 51 and 52 popping up.

52 = Knock sensor, 51 = Switch condition.
Have to replace the shielded wire for the knock sensor most likely.
Need to check and maybe adjust the TPS for the Switch condition, might just be someone moved the throttle while the test jumper was in.

Ok how do i adjust TPS for the switch condition. Is it the throttle position senors? And is the shield wires is connect to the knock senors?

Ok I'm 4runner is running great. I want to thanks to everybody helps me on my Toyota. It's run better now then when I brought it. So thank u guys

Sloped off, what did you do to resolve your issue?