Pull out the chip and reseat it a few times. At this point its maybe the culprit the ecm. The last thing in that diag. Chart says faulty ecm. Did you do all the steps i posted in the helm? Anyone got an ecm this guy can swap in? If youve changed everything in the system and still the code sets its time to atleast consider the ecm.

 

Did i read right you alrewdy swapped out the ecm? Chip and all? If not the chip even stuffing a hypertec in there for a swap test will get you by.

 

.Code 42- est failure .This code will be set when the engine is running at 600 rpm or greater, and there is no pulse on the white wire from the ecm to the*ignition*module*for more than 200ms (milliseconds). Common causes for this code include bad connections, frayed wiring, or broken wires such as the tan/black (ecm pin D5) purple/white( ecm pin B5) or white wire (ecm pin D4). Check your wiring carefully along with the connections back to the ecm.

 

I was referring to changing the Ignition control module, I did replace the computer but not the prom.

 

.CODE 42Trouble Code 42 indicates that there may be a malfunction in the Electronic Spark Timing (EST) system.During cranking, the timing is controlled by the*ignition*module*while the ECM monitors the*engine*speed. When the*engine speed*exceeds 400 RPM, the ECM sends a BYPASS signal to the*ignition*module*which switches the timing to ECM control. The ECM calculates what the timing should be then "tells" the*ignition module*via the EST circuit.An open or ground in the EST circuit will stall the engine and set a Code 42. The engine can be re-started but it will run on*ignition module*timing.The conditions for setting this code are:System in BYPASS mode but the*ignition module*is still controlling timing- or -Engine speed*> 600 RPM with no EST pulses (ECM controlled timing) going to the*ignition module*for*200*msec.Typical causes for this code include:1) BYPASS line is open or grounded2) EST line is open or grounded3) PROM or CALPACK not seated properly in the ECM4) Poor connections between*ignition module*and ECM5) Poor routing of EST harness and/or poor quality ignition wires (EMI induced electrical noise)6) Faulty or incorrect*ignition module7) Faulty ECMhope this helps

 

Your code 42 is either a faulty or wrong knock sensor, or a bad ESC module. If the new knock sensor from Napa doesn't reslove your issue, then get a new ESC module if you didn't already...

 

I havent messed with the EST module, is that the one behind the fuel pump relay?

 

Then get a new EST/ESC, that should do the trick if the new knock sensor doesn't resolve the issue. Both sensors work hand in hand...

http://www.napaonline.com/Catalog/Ca...216_0168412117

 

Thing is after sitting this long just because the weather paks have never been seperated corrosion can set in and break the connection. You have to try those steps posted in the helm. Same book my father used to use and gm techs in the dealerships. Reseat and dialectric grease all connections. Pull all your grounds and ecm grounds and clean and reattatch. Its a simple broken connection or corroded connection. How is the vacume when its idling?

 

19lbs on the 305. 21lbs on the 350

 

yes

 

Ok, im calling around now for one. Just ordered one be here tomorrow. For now Im gonna go out and check the plug going into it since i havent messed with it.

 

http://www.justanswer.com/chevy/2jr9...ing-spark.html

 

Sorry to bombard your post , im just trying to help.

 

Hope that works for you . You have any hair left? Maybe when this is all settled we can all pitch in and send you bottle of champane to celebrate. Lol

 

In the 85-86 TPI cars there's a fuseable link in the wires going from the harness to the distributor. One of those wires may be shorted. One way to tell is the wire will feel like there is nothing in or feel like limp, or rubbery. I got very lucky to find it by accident. I was bending the wires and that particular felt different from the others. I stripped the wire and nothing was in it. I replaced the wire and never had the problem again.

 

Wow you learn something every day. You were lucky on that one. I thought the only fusables were on the starter. Thanks for that info.

 

I'll check that out but correct me if I'm wrong, if the fusible link was blown it wouldn't carry any voltage to the dist. He went out this morning and said it wouldn't even stay running long enough to move it out of the garage.

 

Makes sense. If a wire is not connected you would think that it's not going to start. I really don't think that anything to do with the problem. I really wish I knew where to to tell you to look other than the computer possibly

 

I'm on the hunt for another computer , I turned my original for a core charge for this one. I found a friend who might have an ESC module I can try though. Also I'm gonna change out the coil too. I'd like to thank everyone who has responded in here too.

 

I just read on here that I should have torqued the knock sensor to 14lbs? Anyone heard of this before?

 

yep thats why i said to make sure you dont use the hex part on the sensor to torque it down. if its really tight they are just a b*&#h to get out

 

Well goody I get to jack it back up and get underneath it again hahahahaha. Ill loosen it and torque it at 14lbs. Let me ask, besides the grounds on the back of the drivers side head where else should I check for grounds for this d@mn thing. Is the ECM ground near the computer itself?

 

On the rear passenger side of the head. It should be 3 wires.

 

Thanks, Ill check everything out tomorrow if im home and post the outcome.

 

Did you check the EGR Valve is operationg properly?

 

I actually had someone come test it cause i didnt have the equipment (EGR).

 

Are you serious?

 

........ Did you perform the tests / checks referred to in post #26 & 134 ? ......... Also check the ESC ... Electronic spark Control Module ... not sure where it is on F-bodies ... on Corvette its on the passenger side near the heater box ...

 

Yes, I can clear the codes and restart the car and no check engine light (no codes). The last time is was driven it took almost 3 miles for the light to either flash or come on and according to the chart means its intermittant. As for the ESC I dont know how to check it but I did order a new one, I just got home so I havent been able to mess with it. Tomorrow I plan on taking the harness out of the loom and check the wires all the way to the ECM. One other thing I have to do is loosen the knock sensor up and torque it to 14lbs. Someone did mention that the ECM is grounded on the PS head so I gotta check that too.

 

Re-torqued the knock sensor, checked the grounds, reset the Prom, looked the wires over again and moved all the wires behind the distibutor to get them away from plug wires cause i read that can interfere with EST. Let the car run enough to check timing and re-set the computer, started up good and let it sit and idle for about 30 minutes in the driveway. No Lights! but time will tell tomorrow when he drives it to school, and did I mention I hate this car! hahahahaha Beers on me if this thing is fixed.

 

I know the feeling. I hope that got it for goodness sake!

 

Well it has done good so far on short drives, but he just went to go out tonight and brought it back. He said it acted like it was starving for gas, Looks like tomorrow I will be running codes on this POS again. GRRRRRRRRRRR

 

Ok guys Im done, The car quit again on my son and he kicked the a hole in the side molding so I think this car will be up for sale. So you can read whats been done to the car and see the pics i posted and give me an idea as what to ask for the car. Thanks again, Aaron

 

Damn man that sucks..............

 

Did you try driving it after you kicked it? Really need to take this to a certified gm guy. Its something small and stupid, it always is the most minor thing overlooked. Take a step back and take a few days off it. Might clear your mind. Take care..