brokevayota

im new and have read threads for hours and hours but cant find any help so here it is ... bout 90 4 runner v6 auto from buddy and ran very poorly wouldn't hardly make it up to 50mph found front injector on the driver side was not working so replaced it and the tps bc codes said it was bad .have heard that it will run with out tps is this correct ? and now still have code 51 but very poor gas milage like 9-10mpg and black soot out of the tail pipe very poor acceleration and feels like a small miss at very light throttle have replaced plugs wires cap and rotor. ideals around 1500 have replaced the intake tube and have checked for vacuum leaks found none .. have found that the pcv valve is been taken out and a plug put on the valve cover and the hose could that make a lose of power

thook

Holy crap. Get a PCV valve on there as soon as possible. Just run a google search on PCV and you'll see why you need that. Yeah.....that could make it lose power. But, it could also be due to the TPS issue.

Yes, the vehicle will run without a TPS, but it won't right. IOW, the ECU utilizes TPS to help control spark advance (timing) and injector pulse duration. It's more complicated than that, though. If you're interested in doing some reading on the technical aspects, I'll provide a link at your request. Otherwise, I'd say you could get away with it, for now, but I'd look at getting one as soon as you can.........that is if the TPS is actually bad. Just because you get the TPS code (did you get a code 7?) doesn't mean it is bad. It could be a problem with the circuit.....ie. the wiring. The fact that it's idling around 1500rpm could very well mean that the ECU is simply not getting the needed TPS (IDL contact in the sensor) signal. You'll need to test the TPS. If that passes, then test the wiring at the ECU connector. Of course, a visual inspection is never out of the question.

I really don't know anything about code 51. I did a little searching on what that's all about, but didn't find anything that was really definitive. I'll have to get back on that, if no one else. It'll be a learning experience for the both of us.

thook

Actually, when I think about it, I'm more inclined to believe all code 7 means is that the ECU is getting no signal from the TPS. Because, most of the time people don't even get a code when the TPS is bad. Although, it does make the vehicle run poorly.

Anyway.......

brokevayota

thanks the 2 wires on the ends of the tps have been cut and are twisted together im thinking that could be the problem bc if i'm correct it uses resistance to tell the ecu how much throttle is being used .. on the pcv valve i'm not sure witch hose goes to in i have one that has a 90o turn on it i'm assuming thats the one that goes up to the valve cover ? and if that hose in unhooked does it have vacuum on it ? would the tps and pcv valve possible make it get such bad gas milage like 130 miles per tank i can see around 200 bc it has 33-12.5 and 4in lift stock gears with lockers but should it hurt it that much ? thanks for the help man

brokevayota

and i got codes 41 and codes 51 now that i have put a new tps on it i get 51 i need to adjust it but have to get a meter so i can set it with the feeler gauge or is they a easier way to get it close ?

brokevayota

any help ?

thook

The ECU uses voltage, but resistance in the wire affects the amount of voltage that can pass through. In the case of the wires being twisted, too much resistance will equate to improper voltage signal. Or, it may not be making good enough contact and you'll get intermittent/unsteady signals. You'll need to remedy that before you can make any headway getting the ECU to read the TPS correctly.

In lieu of using a meter and feeler guages, you can simply loosen the TPS and turn it back and forth (with the vehicle running) until the ECU registers the idle set point. It'll be somewhere in between around the middle. You'll notice it because in one direction the idle rpm will go up, and then immediately opposite the idle rpm will go down (or vice-versa, depending on which way you being turning it). You want to set it on the low rpm side. But, you can only do this and count on this method working for you if the wires are in good shape......meaning, you'll need to solder those wires together. Even then, this will not indicate if the TPS is in good shape. You may have a good idle circuit, but then the throttle angle circuit could have bad spots. If the vehicle runs right after this, though, then it's probably fixed and your TPS is probably good. If it still doesn't run right, you might just want to go ahead and check it with a meter. Knowing for sure if the TPS is good will save you chasing your tail. Then, after you've soldered the wires, you'll need to recheck everything at the ECU to make sure the solder worked and there aren't any signal dropouts to the ECU.

TPS inspection and setting:http://personal.utulsa.edu/~nathan-b...93throttle.pdf
Checking TPS at ECU:http://personal.utulsa.edu/~nathan-b...e/102engin.pdf

On the ECU page, you'll see the charts. TPS testing begins on pg EG2-256 at "IDL-E2" and "VTA-E2". IDL is the idle set point and VTA is throttle angle.

TPS and PCV issues will definitely affect mileage. In the case of your PCV valve, it has to open to allow crankcase gases to escape. (Did you run that google search on PCV?) If the vacuum hose is not connected to the valve and also the plenum, it won't open. Then, damage can occur inside the engine.

Here's a good link on PCV:http://www.autoshop101.com/forms/h63.pdf
On TPS:http://www.autoshop101.com/forms/h33.pdf

It's probably safe to say the hose in question is your PCV hose. I can't say for sure without seeing, but if it fits....<<<ding, ding>>>...you probably have a winner.

brokevayota

why i have the upper intake off is they any thing else i should look for ?

brokevayota

im am fixing the wire problem today and jw im thinking my motor is out of a 88 not for sure the but when i bought a tps for a 90 model i had take it back bc they were different and one from a 88 was the same as mine i dont no the history of the motor and when i look at throttle bodies on here for a 90 they do not look like mine at all could there be any thing that could have been different from a 88 motor to 90 that i need to check thanks the the help

thook

I'm not really sure on all the differences there. But, here's the deal. If the motor's from an '88, as long as all the components you get to replace any broken ones are for an '88 and your ECU is for an '88, then there won't be any issues. You'll simply have an '88 motor in '90 chassis. Chassis electricals, if any of that is of concern to you, are seperate from the EFI system.

Make sure of what year engine and ECU you have by checking the VIN on the motor and part number on the ECU and then call a dealership. If the ECU is for a '90, ask them if it will work for the EFI system for an '88. I'm not 100%, but I think there were differences in regards to electrical specs for certain components......like required voltage and what not.

brokevayota

soldered the wire back together and shows no codes but when jumped to set timing it does not idle down and when running if i jump it over it flashes no codes but if i rev the motor above idle code 51 comes up . maybe one of the wires is not making connection and when it thinks there should be a signal there isn't and thats why it throws code 51 ? drove it about 30 miles today seemed to run a little better and get better gas milage then turned it off to clean it and again went back to stumbling when i press the gas down then when it get higher in the rpm it seems to rev better any ideas ?

thook

The idle not changing is an indicator the ECU's not getting a TPS signal. As well, I don't know where I got that you had a code 7. I think code 7 has to be for a different year to indicate no TPS signal. The code 51 you're getting means the same thing, though.....the ECU is getting no IDL signal from the TPS. This is what controls your idle, as well some other things. You need to do some testing following the instructions in the links I posted above.

thook

It is. I looked it up last night. Seems there are some changes in which DCT's are for which after a certain year. Not sure which year that is, though.

Thanks for chiming in.....

XXXsmoochXXX

brokevayota

thanks guys well new update drove the ol yota to work and started to seen a lil funny under load and rev slugish and cut it off at the house came back 30 min. later would not start or even act like its going to cut key on and off a few times and will fire up for second then die like 5 seconds of running maybe and its not getting spark so coil or ignitor lol .. it was idleing a little over 1000 about 1200 or so today but now i guess im lookin for coil or ignitor and have code 14 witch is coil and ignitor ill keep ya posted after i get on ..

brokevayota

one ? will a coil or ignitor off a 4 cylinder work on my v6

thook

Nope.

BigSwole

hey did you ever figure your code 51 issue out?

DEATH RUNNER

I tried that =fail ran great till 3k rpm then fell on its face