Joelong258

I have a 88 toyota that i bought and put a motor in the motor came from a 86 toyota efi. It doesnt run right and im trying to figure out if its cause it has a 86 efi harness plugged into the 88 body harness. Is there a difference in the efi harnesses?

mountaingoat

Don't know about the harness, but somewhere in mid-88 Toyota went to a high-impedance injector. The pre-mid-88 injectors required a resistor.

If you have the resistor on your passenger-side fender, you should be set. If not, might want to look into that.

I'm assuming you're using the '86 injectors with the 88 ECU and harness? Did the plugs on your injectors fit ok?

Joelong258

i bought the whole motor trans and transfer case complete and put it in so everything including the injectors on the efi is from a 86 model i even have the 86 computer. I have all the efi stuff from the original motor EXCEPT the harness. there seems to be no thing to check the check engine lights on the harness too

Flash319

89 is when stuff changed that I have found. Injector plugs are different when they changed to the newer style. If your stuff plugs in to the old injectors then it is right.

toyota4x4907

Maybe you should explain HOW it doesnt run right.

Joelong258

Well it is weird sometimes I can turn the key and
The truck fires right up but when it does it seems like its in a limp mode
Or something like that it will barely idle and won't rev over 3000 or so rpm and othe ones the truck will turn over but just wot start at all. I'm also confused as to where the thing for the diagnostics It isn't in the harness anywhere I see.
I've checked wire connections grounds ignition coil distributor plugs battery fuel pressure switched pcms has fresh gas and new fuel filter checked timing miltiple times but truck barely will idle lomg enough to use a light on it. This is all on a rebuilt motor bored .20 over with new head cam oil pump seals and gaskets so I'm really at a loss for what's wrong or what to try next on it

Kiroshu

Egr valve stuck open and or diphram leaking exhaust gases at all times into intake? Unplug vacuum line to egr and see if it helps.

Terrys87

iTrader: (1)

86 and 88 injectors are not the same. Differences link....https://www.yotatech.com/forums/f116...ectors-127606/

How to get Check Engine Codes. I just put this up for others. Applies to 87 and up. 86 and older is the bottom picture.


The Diagnostic port for the 85-86 is on the Drivers side inner fender and is nothing the same as the 87 and up. Here is T1 and E1 jumped. The codes and engine flashes are the same as the rest of the trucks on the dash.

Joelong258

What of the hoses should i undo on the egr valve or the diaphram. Its one of the last things i havent messed with on the truck and i am suspicious of it maybe causing a problem but i am unsure of what to test on it.

and i have a 86 motor and efi but a 88 body so where would my diagnostic port be at? cause it isnt on the right side fender connected to the fuse box like the 88 efi was.

Terrys87

iTrader: (1)

You having an 88 body, it will be on the Passenger fender attached to the Fuse box. It can be seperated from the Fuse box so shouldnt be far off. It is about 1 1/2 long by 3/4 inch wide.

If by chance they used the 86 harness it will be on the drivers fender and is the smaller of the two plugs shown.

On the link provided Post 42 and 43 are some examples of how dirty it will be and how I go about fixing it...https://www.yotatech.com/forums/f199...99/index2.html

On your EGR, I have never had to replace one. Most just need a good cleaning. There will be carbon everywhere. I make a block off plate out of some thin metal and place it between the EGR pipe and Plenum.

Joelong258

its a 86 efi harness and the rest of the harnesses are in the truck so they are 88. I know there is no diagnostic thing on the right side i know where they are an its not there so im unsure

nv4runner

It is also possible that you just don't have the correct vacuum line hooked up to the EGR valve. I made that mistake after doing the head gaskets on my 3.slow. Figured out which line goes where and fired right up and kept going strong.

Joelong258

well im sure this gets asked alot but does anyone have any GOOD pictures for vacuum lines or write ups that would help show what goes where? ive looked all over the internet used a haynes manual and alldata to get pictures and try to have the stuff hooked up the egr valve i thought was right when i put it all on but its possible its wrong. i feel like many of the pictures i get are different looking than what my motor is..My motor also has a "vsv" at least thats what its labeled in diagrams and i am kinda unsure of where it hooks up to too