Carb to EFI swap, crank, no start

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Ryno5150

Ryno5150

Joined
Apr 28, 2010
Threads
27
Messages
146
Location
WA
Keeping this as short as possible, yet having as much detail as possible. My 89 2WD, did a carb to EFI
swap, all donor parts from a 94 (so that is what it said on ebay). Wiring installed, soldered necessary
splices - went off of 1994 FSM wiring diagram. It all seems to come down to the wiring to the circuit opening relay. I swapped in a known good relay from my 85 4Runner, no change.
At start position, I get 8.5 - 9V to the circuit open relay. Key in run position, I get 12V to the ckt open relay from the main EFI relay. The AFM connection at the ckt open relay is good. Voltage will not cross the
relay to the fuel pump wire. I get fuel pressure if I manually apply power to the pump wire. I get spark, the injectors are getting the ground signal from the ECM. Even if I energize the relay to close the contact inside the AFM, apply direct power to the pump, the vehicle will not start- yes, the air intake tube is on and secure. I checked distributor to make sure the rotor is at cyl 1 on TDC. I studied the FSM wiring diagram like I was studying for the BAR exam before soldering wires.
If anybody has any suggestions, please help. The 4Runner is doing daily driver duties now; I want my 2WD back for good gas mileage and working AC. I also want to leave the top off the 4Runner and bring it out of the garage only on sunny days.
 
Did the donor come from an automatic? And is yours a manual? If so you have to bypass the neutral start switch. Does it crank like it's trying to start or just do nothing?
 
It cranks just fine, just won't fire up. My vehicle is a manual and according to the wiring colors in the ECM connectors, it appears the donor is a manual. Just because the wiring diagram says so, doesn't make it so. I'm no stranger to that happening. There are 3 hanging connectors off the main engine harness that are not in use, 1 blue, 1 gray, 1 brown. I think one of them is to the EGR temp sensor (I'm doing an EGR block off: as you know, living here in Atlanta metro, emissions cut off being 25 y/o cut off) so that won't be used. I will have to study the wiring diagram again. If one of those is for a P/N switch then I will have to jumper it. Thanks for the replay.
 
Yeah if there are 3 big connectors down on the passenger side that are not being used it was probably an auto. Can't remember exactly what they look like but I was thinking that one was white. They were pretty big connectors.
 
They are not big connectors. All 3 are 2 pin connectors. I will have to check my wiring diagrams as well as ohm them out to see. My 4Runner was an automatic, I swapped in a W56, so of course I had to wire a P/N switch override. That was a 2 pin connector. Once again, thanks for the help.
 
All 3 of those 2 pin connectors go to VSVs - EGR, AS, FPU
 
Just a little more info for anybody who wants to jump in here. I was putting a little fuel in the intake, then trying to start (of course put the air intake tube back on). Didn't sound right. Pulled the valve cover to check timing, distributor was 1 tooth off. Adjusted, tried again, would fire up just fine, but of course no fuel supply. Put power straight to fuel pump, still would not stay running. I did voltage checks at all the ECM pin outs, everything within spec. Checked resistance specs at AFM, all within spec. This is getting frustrating.
 
Since you are already aware of the fuel pump cutoff being part of the AFM and you have tried to get it going with the fuel pump test connector jumpered. All I can suggest is jumping the fuel pump and checking your fuel pressure. I'm not sure if you can mix up the feed and return lines on a 22RE but a pressure test would be a good place to start.
 
I have jumped the relay and put power directly to the fuel pump wire (new fuel pump, I can hear it hum, get fuel pressure at filter, get fuel pressure at
cold start injector line), I have not taken the pressure reading, but It comes out strong when I loosen a bolt to the fuel filter.
 
Getting a pressure reading at the fuel rail would be helpful. At least fuel is making it there. You are sure the injectors are firing? A noid light set could verify as well as a stethoscope. Aside from that all I can think of is the fuel pressure regulator or maybe the TPS is totally wore out?
 
I know the injectors have B+ (on same ckt as ignition, checked with volt meter), and when I hooked up my test light to the ground side of the injector harness and watched the light flash when cranking the engine, so I know the ECM is commanding ground. I haven't had time to mess with it in the past 2 weeks. This is all stuff I have already checked.
 
Thanks for the suggestions. Hopefully I can find some time to look at it this weekend.
 
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