Are you not getting fuel to the throttle body? Or are you not getting any injector pulse? BIG DIFFERENCE!
If you have lost injector pulse and spark at the same time, the most likely cause would be a failed distributor module.
Code 34 for that vehicle is "MAP Sensor Signal Return Circuit Low". NO, this will NOT cause your engine to not have spark or injector pulse. The MAP sensor is on the left side of the air cleaner housing on your truck. If you have had the air cleaner removed and the MAP sensor unplugged wile you were cranking the engine (looking for spray from the injectors) THIS is the reason for the MAP sensor code.
As I said in my original post:
If you have lost injector pulse and spark at the same time, the most likely cause would be a failed distributor module.
OK, you said that you had replaced the "ICM" I assume you mean Ignition Control Module. Advance Auto Parts lists "ignition module" as what I call a "distributor module". Some chevy engines have BOTH a distributor module, mounted INSIDE the distributor AND an ignition control module, which mounts next to the ignition coil. This does not apply to your vehicle. Your 2.8L ONLY has the distributor module (Which Advance calls an ignition control module) If this is what you replaced, then what we need to do is to start over from SCRATCH.
All you really need to check this ENTIIRE system out is a test light and a digital multimeter.
It might be a little slow doing it this way, but it will be ACCURATE and PRECISE and we WILL find the problem if you can hang with me and follow my instructions.
First, the injectors have four wires. Two are POWER wires and two are CONTROL wires. The ECM1 fuse supplies power to one injector on the RED wire and to the other injector on the WHITE wire. The DARK BLUE wire and the DARK GREEN wires go to the Engine Control Module (ECM) the ECM provides the ground for the injector to fire it.
The ECM1 fuse should be HOT anytime the ignition switch is in the RUN or CRANK position. Check the RED and the WHITE wires at the injectors to see if they have power with the ignition switch on. If they do not, check the ECM1 fuse. DO NOT just LOOK at it to dee if it is blown. Use a 12 volt test light and check to see that there is power on BOTH SIDES of the fuse If there is power on one side, the fuse is blown. If there is no power on either side, you have a problem with the circuit between the ignition switch and the ECM1 fuse.
The ECM1 fuse is located in fuse position 10 in the fuse block. PLEASE NOTE that It may be labled "ECM IGN" or "ECM1" or it may just have the fuse position "10" labled on the fuse block. Sorry, Chevrolet is not real consistent here. The wiring diagram says ECM1 but the fuse block detail says ECM IGN and the graphic of the fuse block only shows fuse positions. At least they, all agree It is a 10 Amp fuse.
Check this out and get back to me. If we need to continue, I will walk you through it so you can get this thing diagnosed and not waste any more money on parts.
OK, Maybe my instructions were not clear. If you have power at the RED and WHITE wires, then the fuse HAS to have power on BOTH sides. (Unless you removed the fuse to test for power) You should always test fuses by probing the little metal tabs on the top of the fuse. That is not important now....the main thing is that you HAVE ignition voltage to the injectors. There was really no reason to test the fuse if power was present at the injectors...
The next step in checking your injector circuit is to check for an injector control signal from the PCM. Take a paper clip or a pin and "BACKPROBE" the control wires at the injector connector. Backprobing is where you slip a paperclip or a pin into the connector from the back side (the side the wire goes into) so you can make contact with the metal pin inside the connector. Leave the injector connectors connected to the injectors. Take your test light and connect one end to battery NEGATIVE and connect the other end to the backprobing pin. When the ignition is turned ON, the test light should light up. When the engine is CRANKED, the light should BLINK.
If it blinks, your injector circuits are ok and we need to diagnose your FUEL DELIVERY system. If it does not blink, we are going to leave the FUEL INJECTOR CIRCUITSfor right now and do some testing on your SPARK CONTROL CIRCUITS. We may have to come back to the injector control circuits later, but we will test the things that both systems have in common first.
Let me know if the test light blinks.
Why are you asking me??? If you want to just keep replacing parts, knock yourself out!
There is not much I can help you with at this point.
I'm having the same problem......no pulse...does have power.
what can i do to fix my 93 s10 2.8 so i dont have to spray starting fluid to start the truck
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It is not flooded, is it?
Then take a deep breath and wait for awhile.
Kolbrun
SOURCE: 82 corvette crossfire injection, engine
Please go to the crossfire injection forum to get some straight answers to the 82 corvette CFI system and how to troubleshoot it properly. There's a lot of misinformation given here, so much so, I don't know where to begin.
One thing is, the 82 corvette CFI does NOT have a MassAir Flow sensor system, it uses MAP and O2 mostly. The CTS sends a signal to the ECM telling it what the temp of the motor is and in turn the ECM controls the amount of fuel being dumped. On the older (orignal) CTS sensors, they have one wire and takes its ground from the threads. If any coorosion takes place, usually the CTS will report a cold engine and request lots of fuel.
To repair this issue, install one of the newer style CTS sensors that have two wires, one for signal and the other is ground.
Fuel pressure and vacuum leaks on any CFI motor play key roles. Set the FP to 14-15psi measured inbetween the TBs. The regulator is located on the rear TB and must be slightly moded to make it adjustable and can be done in a few minutes.
SOURCE: wont start has fuel and has spark
RC ralston
Your problem is a leak in the cpi pletium most likely the pressure line has a leak
had same problem with mine $45.00 PRESSURE LINE KIT AND $15.00 GASKET FOR PLETIUM and 2 hours labor problem sovled.
You can remove vortec cover and remove air regulator to look inside pletium. I had gas vapor on driver side . that is where fuel lines are. fuel regulator is on passenger side. turn key on and look in hole and see where fuel is spraying. taking pletium off you can again turn key on and make sure where fuel is coming from.
SOURCE: Idle drops really low then returns to normal afew times b4 cutout
my buddies 94 350 has been doing the same thing for years i think its in the computer i would say youll probably have to live with it
SOURCE: 89 Corsica: no power, hesitates in drive, idles
Check your fuel pressure, and or injectors. You may have too much fuel getting into the engine causing it to burn rich and overheat the converters.
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II'm not getting any out of the injectors I checked the codes I got a 34( the map )would that be it?
I can't seem to find any info on the distributor module, or a replacement part? Could you find the part I need on advance auto and post the link? And where would I find it under the hood?
I have power to both the red and white wires and power to the one side of the ecm1 fuse spot
I changed the coil can it started and ran it idled badly but ran and smoked, could it be smoking cause I sprayed starting fluid in in ? And I think the idle is bad cause I changed the idle controlle valve and I may have installed it wrong. Anyhow I took it to the store and it left me sit again and woulnt start
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