SBEC injector strategy question
I have been trying to get the electronics on my project sorted out. I have finally gotten the SBEC to "wake up" with the HEP input from a spare turbo distributor. Everything seems to work properly, ASD turns on and coil will fire from the distributor spin. I connected the fuel pump to the feed with a jumper from the bulkhead connector to the left side body harness and put some ethanol free premium gas in the tank. Fuel pump runs, system pressurizes and once I replaced the leaking injectors I have a nice cone shaped spray pattern on all 4.
The problem is, they appear to all be pulsing together, rather than 1,3,4,2 for the sequential system. The question I have, is this a limp mode strategy due to not having all the sensors connected (this is 2 piece intake). I do not have TPS, Air Charge Temperature, knock sensor or O2 connected. The first 2 because the top half of the intake is not installed. I can't do the "key dance" as the dash is not installed. I do know that Ford had a limp mode on their DIS V6s that simply switched to batch fire if the cam sensor signal was lost.
Re: SBEC injector strategy question
Ok, temperature got up to around 57° F today so I tried using the starter to turn it over. The injectors are all 4 firing together, pulsing so they are obviously not grounded. Tomorrow I can see if my little hand held scope can see the signals from the two HEPs while cranking it (plugs aren't in right now) I will have to pull the fuel rail back off so I can watch the injectors.
I did connect all the sensors up before testing.
Re: SBEC injector strategy question
Here is a link to what your HEP signals should look like.
http://www.turbo-mopar.com/forums/sh...=1#post1144004
Re: SBEC injector strategy question
I had seen that one when I was searching for further information originally. Thanks! Depending on what I find I may have a failed one (or two) for his further testing. I also may have an answer as to what happens with a bad sync HEP.
Re: SBEC injector strategy question
If you have a bad HEP, you can fix them. The fines wire break at the pinch point,
I have also have also made a HEP test jig for bench testing from an old EFI dizzy.
http://www.turbo-mopar.com/forums/sh...=1#post1142632
Re: SBEC injector strategy question
The interesting thing, looking at that thread, the early 2.2L carbureted engines had a strain relief clamp attached to the distributor body, but it vanished about the time the system changed from rotor mounted vanes the shaft mounted.
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Re: SBEC injector strategy question
Didn't use the scope, battery needed charging. Did try with the sync HEP unplugged, no injector trigger, so that eliminated one possibility. If we have some tolerable weather again, I am going to disconnect the jumper for the fuel pump and jumper the ASD to keep it on and with the SBEC disconnected try grounding K11 - K14 one at a time and see if one or all injectors actuate, if one, then there is an SBEC issue, if all, then it will be a wiring issue.
FWIW, here is the scope and test leads I made for the HEPs.
http://www.turbo-mopar.com/forums/at...id=63697&stc=1http://www.turbo-mopar.com/forums/at...id=63698&stc=1
Re: SBEC injector strategy question
Ok, got a bit warmer than predicted today. ASD jumpered, no SBEC connected. K11, K12 solid to chassis/battery ground. K13, fires injector #4, K14 fires injector #3, K15 fires injector #2, K16 fires injector #1. This verifies the harness wiring is correct from injector plug to the SBEC 60 pin plug. Therefore, problem must be in the SBEC.