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So I drove it to work fine then go to leave it wont start. I have replaced the igniter and coil, distributor, and efi relay. There is no power to the switch side of the efi relay or the +b or +b1 on the ecu not sure what else to check/replace
It won't start...meaning it won't crank, or it cranks fine, but won't fire up?
Enquiring minds need to know
Do you have an FSM, with the schematics in the back? If not, get one!
Is there voltage to the input side of the EFI relay, but none out? Are you making sure the EFI relay is energizing when it should? Is the COR energizing during the start sequence? Do you have the correct voltage in, and out of the COR?
The trick is to look at the schematic, and start about 1/2 way through the circuit you're having trouble with. Is the reading at that point good? If it is, move about 1/2 way farther through the circuit, and test. So at about the 3/4 point.
If the reading was NOT good at the 1/2 way point, back up about 1/2 of that, so to about the 1/4 point in the circuit. Is the reading good?
You see the pattern, here? Just keep splitting the circuit left in 1/2. Eventually, and rapidly, you'll zero in on the bad part, you see?
But you need a good schematic of your systems, of course. Yes, I spent my entire working life as an electronics technician
Just hope it's not a corroded wire or connection. Those can be a PITA to find!
Sorry yes it cranks and fuel pump kicks on just no spark. The relay works but only has power at the battery side it gets no signal from the switch side and the check engine light doesn't come on
If the EFI relay has power to the "battery side" (pin 5), but no power to the "switch side," (pin 1), then you should first check your IGN fuse (use a multimeter to each of the metal tabs on top of the fuse with key-on; you won't be the first person to mis-identify a blown fuse as "good"). If you have power out of the IGN fuse but no power at EFI relay pin 1, then it's a wiring issue. If you have no power to the IGN fuse then you should check IG2 (pin 7, wire is B-R) out of the ignition switch.
One thing to consider is the possibility of a bad socket, for the fuse or the relay or both. Sometimes, when a fuse is "robustly" pulled and replaced, the socket can be spread to the point where it makes poor contact, intermittently. You could remove the IGN fuse and EFI relay, then using a test light at the relay socket and a jumper at the IGN fuse, see if you have continuity.
If i jump it this way the check engine light turns on and if i also jump it across for the fuel pump to kick on it will start but run rough and wont really rev
oh and the tack still wasn't working
Last edited by zmapro2003; Mar 26, 2020 at 06:32 PM.
If i jump it this way the check engine light turns on...
And what code does it read out? This could lead you to THE problem. Not saying it will, but it could.
The FSM has troubleshooting flow charts for most of the codes the CEL gives. They may not take you to the final problem, but they may lead you, again, in the right direction.
From everything you shown so far, I would try the EFI relay first, and, if that's not the trouble, then trace out the wiring's continuity with a decent multimeter. A little trick to that: you can find another wire that runs the same way, roughly, and short them together at one end, then ohm them out at the other. If they're reading continuity, the wire in question is good, obviously. If not, well, ONE of the two, or both, are bad. Only problem with that method
A way to make life easier when ohming out long wire runs, make a LONG jumper, just a long piece of 12 Ga wire, with alligator clips at both ends. That way, if your meter leads don't reach, you can clip your jumper to one end of the wire being tested, and then to the other lead of your meter to the jumper. Obviously, one lead of the meter will be on the wire under test. This way, you don't need to have someone hold a meter lead, that may reach or not, on one end of the wire for you, see? Si` !
Also, if you just ohm one at a time, don't forget to flex either the single wire you're testing, or the whole bundle it's in. Bad wires may not show up unless they're flexed a little, or a lot. If you find that's the problem, now you have to identify just where you have to flex to get it to go bad. It can be a long process.
Finally, make sure to check all plugs involved very carefully. Wires can pull out for a plug, on either side of the plug/receptacle pair, but still LOOK like they're fully installed. A small tug on the wire will let you know if it's loose in the plug. Also, check the plugs for corroded/dirty connections inside. It happens. Happens a lot on the headlight plugs right at the headlight bulbs. They right out there in front of everything. Not YOUR problem, but it's an example.
If i jump it this way the check engine light turns on ...
This is normal; the first thing that "happens" when the EFI relay closes (powering the ECM) is the CEL bulb-check. If the light stays on after the engine is running, that's a code.
You sound like you have a lot of broken wiring; the EFI relay is not getting the IG2 signal, your COR is not getting the STA signal, your tach isn't working, and who knows what's causing your rough running. If it were me, I'd work on the wiring first.
Mar 26, 2020 | 01:14 PM
