Code Reader Issue - ZR-1 Net Registry Forums

ZR2 · 09-17-2020

I was starting a plenum pull today as I have at least one bad coil and decided to see what codes if any were present, no lights on etc. but wanted to check and also see what a live data stream looked like prior to fixing the coils etc. I previously had a 91 ZR1 and my code reader, (Actron CP 9190) worked perfectly with it. It has all the attachments for all different models etc. I did notice that my 94 ZR1 has an OBDII connector below the steering wheel to the right side. I guess I was expecting to see an OBDI connector. My issue is that when I hooked up to the connector it seemed to work fine and then very quickly it just basically says it has lost connection. I tried it several times and it would knock me out pretty quickly each time. I will double check my connections, but felt like they were all solid. Any ideas? Thanks Mark

ZR2 · 09-26-2020

I went back to work pulling the plenum as I knew I had a bad coil. I hooked up a timing light and sure enough the number 5 and 8 were not flashing the same as the rest. I managed to get the plenum off tonight, before picking up carryout.....but that is a different story. So I got to the coils and removed all 4 of them and decided to test them with a multimeter. I looked them over and did not see any obvious signs of cracks or burns etc. so I put my multimeter on ohms and tested between the two plug towers ....at first no readings then I tested a new one and got 5.5 thousand ohms I guess is where the setting was. Two of the 4 coils tested out the same as the new coils and two of them were in the 300 range? The one I knew was bad and another one. 5 and 8 were bad and also 1 and 6. I am no expert with a multimeter but I know it is telling me where my issues are. I also bought new wires and new injectors. I now am wanting to get this done so I can really feel what all the HP feels like. Amy thing else sensor wise or other that I should replace while I am in there, Ni issues with the starter. Cranks over beautifully with no strain or noise. Thanks Mark

DRM500RUBYZR-1 · 09-26-2020

1- make sure that the rear drain hole is clear
2- make sure that all vacuum lines are tightly connected.
get it back together
and
SMILE!

Marty

ZR2 · 09-27-2020

Marty, Agreed. I was slated to going to the mall today with my lovely wife.........but it was rainy here enough that she said I was off the hook. She did some local shopping and me...... decided to get some ZR1 work done. I pulled the injector rail with injectors attached and got it on my bench in garage. I will try and upload some picture of close up of injectors. When you loo at the injectors 8 have a blue ring at bottom and 8 have a white ring. There is a definitive difference in how clean the tip area is between the two sets of original injectors. The primary injector tips looked reasonable clean. The secondary injector tips are the dirty ones. The primary injectors have a white ring at the top near the fuel rail while the secondary injectors have a blue ring near the rail. I believe that there are the original injectors as the car has the original wires and coils etc. Once the injectors and rail were removed all the lower o rings stayed in the block and man was it dirty and just filthy. I vacuumed it out and pulled out the O-rings and then cleaned out the injector holes in the block. Pictures to follow.

ZR2 · 10-03-2020

Finally, getting back to putting the plenum back on. I replaced all the injectors with FIC injectors. They are really high quality and a direct plug and play. Nothing needs to be done to make them fit etc. Ordered them from Jerrys gaskets along with all the required gaskets. Also, replaced the plug wires with the replacement set from GM. They are almost identical, but do not have the cylinder number on them or the LT5 printed on them. All new GM coils went in a I actually think I had an issue with 2 different coils. I had the coils issue after changing plugs????? Maybe an increased gap made the coils work harder and they weren't up tp it? Much smarter guys on here than me, so I replaced all the coils. Today got the coils in and the plug wires routed and installed and also the fuel injector rail. Getting there, you would think today I would have enough time to finish, but you know how that goes. The original coils had the stamps on them with what corresponding cylinder it was firing or plug wire attachment. I wrote on the new ones with a white sharpie. Not as neat but.....works.

Paul Workman · 10-04-2020

Well, congratz! A plenum pull is a ZR-1 "rite of passage". For the record, you might record the resistance between the plug wire poles. All should read approx the same: any magnitude difference either way indicates problems and need for replacement.

Injector resistance is typically measured when at/near operating temperature and most brands I've measured read ~14Ω (hot!) and a few read ~12Ω (hot). FYI, an injector reading a couple Ω lower that the rest is an indication a few internal windings are shorted together. And, by the time one reads 4Ω lower that the rest, it for sure indicates not only that one should be replaced, but ALL of them "while your in there" b/c it is only a matter of time B4 you'll be in there again for another injector(s).

As far as the secondary injectors getting dirty goes, always running in FULL POWER mode, especially at highway speeds, will go a long way toward keeping the secondary injectors clean(er). (A topic for another time/thread)

Enjoy!

ZR2 · 10-05-2020

Paul, I appreciate it. I actually did a plenum pull on another ZR1 that I owned years ago. I actually did it in my driveway at the time. I was younger and dumber back then!!!! I had to pull it off several times when I did the original one as I had a massive vacuum leak the 1st time.......then the 2nd time had a water coolant leak......then the 3rd time was the charm. Yes the memories!!!!

ZR2 · 11-19-2020

Paul, Finanlly got tired of looking at the car in my gagrage......and finished it up 2 nights ago. New Injectors, new wires, new coils (GM) and new plugs. Just had it out briefly, but seems to be running pretty good. (Knock on Wood as we say) Now my regular driver is having issues!!!!!!! Guess I will have to drive the ZR1!!!

WARP TEN · 11-22-2020

Quote:

Originally Posted by ZR2

Paul, Finanlly got tired of looking at the car in my gagrage......and finished it up 2 nights ago. New Injectors, new wires, new coils (GM) and new plugs. Just had it out briefly, but seems to be running pretty good. (Knock on Wood as we say) Now my regular driver is having issues!!!!!!! Guess I will have to drive the ZR1!!!

Gee, it seems like if you didn't have bad news you wouldn't have any news at all! But having to use the ZR-1 as a daily driver sounds like good news to me. I am still driving my Z06 as a daily driver here in Northern Illinois because we haven't had any snow (and the accompanying salt) yet, and the weather until recently has been unseasonably warm. Usually it goes up on the lift November 1 but I will hold out as long as I can this year. --Bob

ZR2 · 11-22-2020

Just had it out today for really what I would say was the 1st voyage of any duration aftre all the work and "Knock on Wood" or my head as my wife would do, it really performed very well. I did need gas and when I stopped my gas cap was loose because I loosened it when I started the process and forgot to tighten it. All gauges seemed prettty happy witrh everything, oil pressure, oil temp and water temp. Maybe the next week or two it will be driven regularly and will see how she performs.

09-17-2020	#1
ZR2 Join Date: Jun 2018 Location: Maryland Posts: 53	Code Reader Issue I was starting a plenum pull today as I have at least one bad coil and decided to see what codes if any were present, no lights on etc. but wanted to check and also see what a live data stream looked like prior to fixing the coils etc. I previously had a 91 ZR1 and my code reader, (Actron CP 9190) worked perfectly with it. It has all the attachments for all different models etc. I did notice that my 94 ZR1 has an OBDII connector below the steering wheel to the right side. I guess I was expecting to see an OBDI connector. My issue is that when I hooked up to the connector it seemed to work fine and then very quickly it just basically says it has lost connection. I tried it several times and it would knock me out pretty quickly each time. I will double check my connections, but felt like they were all solid. Any ideas? Thanks Mark

09-26-2020	#2
ZR2 Join Date: Jun 2018 Location: Maryland Posts: 53	Re: Code Reader Issue I went back to work pulling the plenum as I knew I had a bad coil. I hooked up a timing light and sure enough the number 5 and 8 were not flashing the same as the rest. I managed to get the plenum off tonight, before picking up carryout.....but that is a different story. So I got to the coils and removed all 4 of them and decided to test them with a multimeter. I looked them over and did not see any obvious signs of cracks or burns etc. so I put my multimeter on ohms and tested between the two plug towers ....at first no readings then I tested a new one and got 5.5 thousand ohms I guess is where the setting was. Two of the 4 coils tested out the same as the new coils and two of them were in the 300 range? The one I knew was bad and another one. 5 and 8 were bad and also 1 and 6. I am no expert with a multimeter but I know it is telling me where my issues are. I also bought new wires and new injectors. I now am wanting to get this done so I can really feel what all the HP feels like. Amy thing else sensor wise or other that I should replace while I am in there, Ni issues with the starter. Cranks over beautifully with no strain or noise. Thanks Mark

09-26-2020	#3
DRM500RUBYZR-1 Join Date: Sep 2008 Location: Mullica Hill, New Jersey Posts: 2,581	Re: Code Reader Issue 1- make sure that the rear drain hole is clear 2- make sure that all vacuum lines are tightly connected. get it back together and SMILE! Marty

09-27-2020	#4
ZR2 Join Date: Jun 2018 Location: Maryland Posts: 53	Re: Code Reader Issue Marty, Agreed. I was slated to going to the mall today with my lovely wife.........but it was rainy here enough that she said I was off the hook. She did some local shopping and me...... decided to get some ZR1 work done. I pulled the injector rail with injectors attached and got it on my bench in garage. I will try and upload some picture of close up of injectors. When you loo at the injectors 8 have a blue ring at bottom and 8 have a white ring. There is a definitive difference in how clean the tip area is between the two sets of original injectors. The primary injector tips looked reasonable clean. The secondary injector tips are the dirty ones. The primary injectors have a white ring at the top near the fuel rail while the secondary injectors have a blue ring near the rail. I believe that there are the original injectors as the car has the original wires and coils etc. Once the injectors and rail were removed all the lower o rings stayed in the block and man was it dirty and just filthy. I vacuumed it out and pulled out the O-rings and then cleaned out the injector holes in the block. Pictures to follow.

10-03-2020	#5
ZR2 Join Date: Jun 2018 Location: Maryland Posts: 53	Re: Code Reader Issue Finally, getting back to putting the plenum back on. I replaced all the injectors with FIC injectors. They are really high quality and a direct plug and play. Nothing needs to be done to make them fit etc. Ordered them from Jerrys gaskets along with all the required gaskets. Also, replaced the plug wires with the replacement set from GM. They are almost identical, but do not have the cylinder number on them or the LT5 printed on them. All new GM coils went in a I actually think I had an issue with 2 different coils. I had the coils issue after changing plugs????? Maybe an increased gap made the coils work harder and they weren't up tp it? Much smarter guys on here than me, so I replaced all the coils. Today got the coils in and the plug wires routed and installed and also the fuel injector rail. Getting there, you would think today I would have enough time to finish, but you know how that goes. The original coils had the stamps on them with what corresponding cylinder it was firing or plug wire attachment. I wrote on the new ones with a white sharpie. Not as neat but.....works.

10-04-2020	#6
Paul Workman Join Date: Nov 2007 Location: Squires (near Ava MO in the Mark Twain N'tl Forest) - Missouri Posts: 6,493	Re: Code Reader Issue Well, congratz! A plenum pull is a ZR-1 "rite of passage". For the record, you might record the resistance between the plug wire poles. All should read approx the same: any magnitude difference either way indicates problems and need for replacement. Injector resistance is typically measured when at/near operating temperature and most brands I've measured read ~14Ω (hot!) and a few read ~12Ω (hot). FYI, an injector reading a couple Ω lower that the rest is an indication a few internal windings are shorted together. And, by the time one reads 4Ω lower that the rest, it for sure indicates not only that one should be replaced, but ALL of them "while your in there" b/c it is only a matter of time B4 you'll be in there again for another injector(s). As far as the secondary injectors getting dirty goes, always running in FULL POWER mode, especially at highway speeds, will go a long way toward keeping the secondary injectors clean(er). (A topic for another time/thread) Enjoy! __________________ Good carz, good food, good friendz = the best of timez! 90 #1202 "FBI" top end ported & relieved Cam timing by "Pete the Greek" Sans secondaries Chip & dyno tuning by Haibeck Automotive SW headers, X-pipe, MF muffs Former Secretary, ZR-1 Net Registry

10-05-2020	#7
ZR2 Join Date: Jun 2018 Location: Maryland Posts: 53	Re: Code Reader Issue Paul, I appreciate it. I actually did a plenum pull on another ZR1 that I owned years ago. I actually did it in my driveway at the time. I was younger and dumber back then!!!! I had to pull it off several times when I did the original one as I had a massive vacuum leak the 1st time.......then the 2nd time had a water coolant leak......then the 3rd time was the charm. Yes the memories!!!!

11-19-2020	#8
ZR2 Join Date: Jun 2018 Location: Maryland Posts: 53	Re: Code Reader Issue Paul, Finanlly got tired of looking at the car in my gagrage......and finished it up 2 nights ago. New Injectors, new wires, new coils (GM) and new plugs. Just had it out briefly, but seems to be running pretty good. (Knock on Wood as we say) Now my regular driver is having issues!!!!!!! Guess I will have to drive the ZR1!!!

11-22-2020	#10
ZR2 Join Date: Jun 2018 Location: Maryland Posts: 53	Re: Code Reader Issue Just had it out today for really what I would say was the 1st voyage of any duration aftre all the work and "Knock on Wood" or my head as my wife would do, it really performed very well. I did need gas and when I stopped my gas cap was loose because I loosened it when I started the process and forgot to tighten it. All gauges seemed prettty happy witrh everything, oil pressure, oil temp and water temp. Maybe the next week or two it will be driven regularly and will see how she performs.