pplusent

Bought a basket case 92 4runner. Previous owner damaged everything he touched!
I have now replaced the trany pump, flex plate, ac, pulled and rebuilt the engine, built new duel exhaust system and the list goes on. I am now at the point of starting the 3.0. When it was on the engine stand it had good compression, but now I am showing little to none on the Gage, but I can here the pressure being released from the exhaust which makes me question the Gage (although since I put the engine in, outdoor temp have dropped to freezing and I think the assembly oil on the rings may be to cold and keeping the rings from fully expanding in the cylinders). Anyway I am getting a no start on the engine. I have checked the spark and it is good so I am questioning the fuel injection system. I have a clear line on the fuel rail return so I can see there is fuel in the rail ,but I am not getting any fire in the hole even with starting fluid. All the injectors have been cleaned and are all flowing the same, I just don't know yet if they are getting a pulse. Also all lines have been cleaned and tank cleaned. also replaced filter.
So, I guess my question is what items will keep the injectors from firing? Is there some sort of fuel injector cut off, or are there components that will keep them from firing? O2, relay, internal safety cut out etc. Also the TPS won't return all the way on its own, is this common on these?
If it were American I would have no problem, but these Toyota's are crazy the way they do things, so I'm stuck at the moment.
Can anyone shed some light on this issue?

millball

Have you got all the intake air piping mounted up between the air cleaner/vafm unit and the throttle body??

They won't run unless the ecm gets a signal from the vafm that intake air is passing it.

pplusent

Yes all the plumbing is on it and everything is connected. Although I was just looking it over and noticed after moving the O2 sensor for the new exhaust I forgot to plug it in. Don't know if that will shut down the FI down, but I will see tomorrow.
Goes to show ya, there is always something missed.

pplusent

Oh, since you mentioned it! what is with all the cans on that intake system? Are they supposed to be some sort of partial separator? Seems like it would get rid of a lot of junk under the hood if they were remove and a solid tube ran to the TB from the air cleaner.

millball

Google ISR mod. Lots of people remove the intake silencer box and replace it with some sort of plain sweep between the vafm and the throttle body.

The other piping and boxes relate to the PAIR system--- that is a passive setup that adds atmospheric air to the exhaust during deceleration in order to help the cat do its work.
It uses no engine power.

As far as I can determine, there is little benefit from modding, or removing either of these stock setups.

The Toyota engineers put them there for a reason.

pplusent

So the boxes are for emissions. Just a little bit filling under the hood, would be nice not to be packed in like that.

pplusent

Found the problem, seems the cams were 90 degrees out. explains the lack of compression. Don't know how it happened, checked it three times on the engine stand. Mark on the crank gear must have been wrong.
fixed the timing and it started on the first crank.