4efte wiring issue

[wheeloftime]

Okay here it goes. My son put a 4efte starlet motor into a geo prizm. 1994. Rewired the harness to rhe geo ran perfect. No issues or problems. Several years later we start to do a motor swap. The body of the 1994 geo died so we started putting into a 1997 geo prizm lsi. motor went in. wiring went in starts just fine. The problem is this. She only revs to approx 3000 rpms the cuts back to idle revs up cuts back. engine does not die just wont rev past about 3000. I have checked the wiring to the ecu, I have checked the map senson, I have changed the fuel filter and the fuel pump. Am i missing something?But........................................................

Through research I am learning that the 4efte is used with the obd1 system where the 1997 lsi is using the obd2 system. That is probably causing the issue. Can I add the sensors needed? If so what do I need to add and where. I was told Ganza was the one to talk to here so Ganza if you or anyone else can help I would greatly appreciate it before I rip out anymore hair.

 

[weeJohn]

I assume you are using the 4EFTE ECU as well as the engine?

Check the throttle position switch on the back of the throttle body, there is plenty of info on how to set it up in the tech sections, if you do a search it will help you out.

 

[wheeloftime]

we tried another Tps from another 4efte but it did not fix the issue. I am assuming it is limp mode from the reading I have done. Now this is from a obd1 car ( starlet motor) to a obd2 car geo prizm lsi. Is that the reason it is going into limp mode?
And yes it is the 4efte ecu green sticker.

 

[weeJohn]

If you are using the 4EFTE ecu then the OBD system will be OBD1 as thats what the ecu is programmed for, no matter what the car had originally. It would only be the case of it not working if you were still trying to use some of the OBD2 bus system sensors with the 4EFTE ecu.

 

[wheeloftime]

so does that include the abs and cruise control? I know that is probably a stupid question but I think light bulbs are going off. So If I try to use anything off of the obd2 system it will create a fault because the obd1 cant read it right.?

 

[wheeloftime]

I tried to unplug the abs. The box on the passenger fender, the abs box below the radio, and the plugs to the unit that controls the seperate brake lines. No change. Still no check engine light. Abs light still says active on start up. What did I miss.

 

[wheeloftime]

Have a silly question again. The prizm lsi had a three wire plug on the distributor and the 4efte has a 4 wire. would I need a patch or how would that be wired?

 

[weeJohn]

You need all the distributor, engine sensor and the ignitor wires wired back to the 4EFTE ecu, you will need to use the Toyota parts to get it all to work with the ecu. You will also probably need to use the 4E instrument cluster to work with the 4EFTE ecu. There is no cruise control feature for the 4EFTE ecu so that will all probably need disconnected.

 

[wheeloftime]

Here is a update. We went through the wiring for the 4efte ecu. All wires check out to be where they need to be. Checked fuel pump voltage no voltage drop as the motor cut back to idle speed. . Checked distributor coil and injector wires. Checked map, tps, and all other connectors. They check out fine. No change.
What does the instrument cluster have to do with the car running? What sensor would still be active when the 4efte ecu is installed and wired.? I am at a loss as to how to proceed. This has gone from a easy switch to a nightmare in a hurry. Damb obd system.

 

[weeJohn]

The Instrument cluster is wire back to the ecu on these cars, the check engine light and a few others get their signals from the ecu.

 

[Texx]

Have you tried revving the engine with the TPS connector disconnected?