lyntoolman

hi guys, I've been lurking for a while, with no need to chime in but... a friend just bought a C.E. from Jim-bob (seriously under an awning in front of his trailer) Jim-bob said it had been sitting about 2 years. I'd guess more like 5. Clean body, interior that looks like chickens lived in it.
Friend got a great job offer 1000 miles away. as no good deed goes un-punished, I told him I'd get it running.
We fired it in the carport pouring gas into the Tbi. it started. Then Jim-bob got careless and we had a little fire. only apparent damage was soot.
I replaced the whole in-tank unit ( lord the old one was trashed) I have gas to the TBIs, no squirt out of them and no power to the coil.
I guess my q

lyntoolman

sorry, computer hiccup.... I guess my questions are where did the spark go and when does the ECM fire the injectors? secondarily, what should the connector read when it fires

Easy Mike

FWIW: if it's a CE, it's an 82. 84s are C4s. Both model years have TBI.

lyntoolman

Mike you're right...typo. it is in fact an 82. Seems my fingers were out to lunch yesterday. I have had a few cars, '57, '68, '69, '71, '85. this crossfire mess is whipping me tho.

76C3forme

It's been a long time since I've worked on a crossfire system but I'm guessing it's the same as my old 83 Z-28 with crossfire. Weak or failed oil pressure sensor will cause that. ECM sees reading from Oil pressure sensor and provides spark. It also (I believe) provides the Ground / Negative Pulse to the injector for the "squirt:.

If you can verify you have fuel to the injector "pods" you can manually ground (pulse it, don't ground it steady) the negative wire to the injectors with the key on, and see if you have fuel for a quick test.

(You can loosen the nut for the fuel line or see if there is a schrader valve to see if you have fuel in line. If you don't, that's another issue).. I haven't done it in a while but I know it was almost identical on my 1990 Chevy truck with single TBI. If the system is similar, that may help you out. (I still have that truck so I may be able to take a few readings if needed).

Also, if the car has been sitting for a while, somtimes "just cranking" / and a weak / old oil pressure sensor isn't "quite enough" to signal the ECM for spark and fuel. My old truck used to do this all the time. It would start with starting fluid due to the fact it would "kick over quickly" and the initial higer RPM would compenstae for the weak oil pressure sensor and then I'd get spark and fuel. But it would not start on it's own. It would run all day after being started. Took awhile to figure out.

Other than the Oil pressure sensor, the injectors (which do go bad) but usually not both at the same time), the ECM and wiring is about the only thing left.

68blvert

no spark and no fuel means no ecm pulse of injectors and no grounding of coil control circuit. check power and grounds at ecm. check for clean, square wave form pattern from purple/ white trace wire at the distributor to the ecm. this is the signal ecm uses to fire injectors. make sure tps is not sending high voltage signal to pcm which puts pcm in clear flood mode.

bpassmore

If the check engine is not on when the ignition is on, check the fuse at the terminal block in the battery box.

You should hear the fuel pump run momentary when the ignition is turned on.

lyntoolman

76c3, 68blvert, bpassmore, gave a place to start checking. I confess I haven't checked all the fuses in the block....carpet is THAT nasty. and of course the car is at his mom's an hour away. may have to drag it back to my place just for efficiency sake.
One thing I have been fighting is that Jim-Bob's method of splicing wires was to twist them and wrap it with black tape.

7T1vette

That's a bit better than using chewing gum.... [but not much]