VinhZXT

Did you clean the connectors at the ECU? When it runs like crap open up the kick panel and play with the connectors and see any changes. Do you still have the VCM module hook up to the EGR? if so disconnect it from the EGR valve or better yet just remove the EGR valve and cap it. I experienced this problem before . My car ran rough after warmed up and it turn out to be a bad EGR valve. Good luck

The cog doesn't mate with the drive gear inside the trans. You need to remove the locking nut and rotate the speedo cog housing until it mate with the drive gear. If it mate properly when you spin the tires you can see the center shaft spinning. Put a mark on the speedo housing where the locking tab will be and cut a new slot for it. Good luck

David, Does this mean I can come down to pick up the auto tranny? I am anxiously waiting to pick up the tranny so I can get started as well. ) .. Congrat..

David, haha... I never said I will not buy the tranny from you. It's always good to have an extra tranny for spare hehe.. I am waiting for you to let me know when to come down to pick the tranny up ..)

Tim, I was thinking of doing that too but then again I dont' know the tranny I will buy will last long or not. The tranny I have right now I took it out of a running car along with the engine. I have a friend with the vette manuals. He will let me borrow them to go home and find out. I doubt GM build different 4L60E tranny just for the Vette. I will get a friend of mine from a local junkyard to search for a cheap used 4L60E tranny from the Fbody so I can play with. PS. I would love to put this whole trans axle rear into a Z but shorten the torque axle will be the problem. Also I don't have all the rear suspension and axles from the Vette. It would be nice to have the whole Vette rear end mounted under the Z. I am dreamming hehe

Hi guys, I have this 4L60E auto tranny from the Vette and it is attached to the rear differential. I want to use this tranny for my LS1 Z swap. Does anyone have any info how to convert this tranny back to the Fbody so I can start my swap? I separate the tranny from the rear differential. I think the bell housing from the fbody will bolt in fine. What I am worrying is the rear extension housing. Do I need anything esle or just the rear extension housing? I searched on Ebay and saw someone selling a weird looking piece of rear housing. Anyway I did some measurements and the length from the mounting surface of the bell housing back to the rear of the tranny (without the rear housing) is 15". From here back to the end of the shaft is 9 and 1/2". This means the rear extension housing has to be around 10". From the look of some of the pictures of this tranny from Ebay that looks about the same length. Can someone make some measurements of their LS1 auto tranny for me? Thanks.. I am also posting the pictures of the tranny on my web site. Please feel free to check it out. http://www.cardomain.com/ride/721840/4 Again thanks for any input guys.

lifegrddude, Sorry to hear you still having problems. My car does that when it is not completely warm up and even so if I floor it it will take off. Have you check your fuel pressure at the rail? Sputtering usually not having enough fuel either your ECU is not sending signal to the injectors or you have a fuel clog somewhere. When I trouble shoot my blue ZXT I had the fuel gauge hooked up and that's how I found out I had the fuel clog. I would suggest you to spend $20 to get one from Summit to save you the troubles. With the fuel gauge you can verify the FPR is OK and or your fuel pick up hose in the tank is not clog. If the fuel pressure checks out OK then I would go check the AFM. Make sure it sends the correct signal to the ECU. With the MAF I don't know how you will be able to do a unit test. With the AFM you can do that by measuring the resistence when moving the flap. Good luck V.

KTM, I used to have Jeff's phone number. He recently moved and he changed his number. He frequently shows up at Zcar.com and here. So I hope he reads this and contact you. I have one of his DP and I have to say that Jeff did a very good job designed it and the craftmanship is awesome. Good luck

Burn, I am running 12 PSI on my stock turbo ZXT and I get about the same gas milage as you. If you really want to get good gas milage you have to put in new injectors and replace all the sensors that controls the emission. I had the idle problem with my ZXT also and I tried to fix the VCM and AAC valves and it still not working. I guess the computer is not sending out the signals to control the VCM any more. So I removed all that stuffs and used the small screw under the TB and increase my idle a bit. Currently I am still not completely trouble free. When the car kicks into open loop mode the idle drops a little and I have to keep the idle higher for it not to stall. After it warms up the idle is perfect. My blue ZXT doesn't even kick into open loop at all so the idle doesn't drop. I don't know what your ECU will do but hope you find a good point to set the idle. Good luck Vinh

Foreman, You need to verify if it runs rich or not by checking your spark plugs. If it's rich then the problem is your AFM. Get an ohm meter and check for the impedence of all the wires from the AFM connector to the ECU. You might have a corroded wire that sends a bad signal to the ECU. This inturn will make it run rich. If it all checks out find then read the manual for procedure for testing your AFM. Last but not lease clean up all the connections to all the sensors and ECU. Good luck

I suggest you to replace the distributor first. Both problems could be cause by a bad distributor. I've seen the poping thru the intake happened to my friend's 78 280Z. it turned out to be a bad distributor cap. Good luck

Magnum, Your VCM (Vacuum Controll Module) is bad and it can't control your AAC valve. The AAC valve is what controls your idle. Just use the small screw underneath the TB to increase your throttle a bit. The oil pressure suppose to be low when you are idle. It should increase to about the middle of the gauge when you drive the car. Good luck

This sounds like the AFM is the problem. Unplug the AFM connector and check for resistance of all the wires from there and back to the ECU. Check to see how stiff the flap inside the AFM. If it's too loose then read the manual for procedure to test out the AFM. And last clean out the ECU connectors real good and put some conductive grease on the pins and connectors. Good luck

The last time I talk to Jeffp he still got 1 or 2 DP left. You might get lucky if you contact him ASAP. You can build the CAT back pipe if you have a welder. I just built mine and all the parts cost about $100 and I took less than a day to finish it. You will need a helper. Good luck V.

Innerware, Thank you for the comments. This garage was what kept me busy last year and probably the next few years. The picture only show half of the garage. I got the other half finished and ready to be rent out. Joe, We have enough Z people around S. Philly and S. Jersey. One of these days we will have a Z BBQ at my place if we can find enough people to show up. BTW please give me a call any time when you need a helping hand.

All, Joe beat me to the punch. Yeah it was a piece of cake. The thing that bothers me is that I am very good with electronics and couldn't figure out this problem until Joe showed up. I can't thank Joe enough for coming and helped me today. I had helped many people with their electronics problems before and this is the first time someone helped me solved my problem. Another lesson learned for me. I guess everyone probably anxious to know what was the problem. Joe and I agreed that there was 2 problems. The #1 problem was the tach wire was shorted somewhere and I had this tach wire connected and disconnected randomly. This explained why I was getting sparks intermittently before that. #2 problem was the center contact of the rotor was not making good contact with the point that lead to the coil sometimes. I have to blame the second problem to myself because of frustration and I wasn't careful when putting on the distributor cap and I bend it side way. The main problem was I figured out how everything works but I didn't come up with a good way to test it at each stage. That was what we did when Joe showed up. We started testing each stage starting from the spark plugs. The tach wire was the tricky one. It had Joe confused for a bit but Joe immediately came up with the solution. Pete, I tried your suggestion as well and connected 12V from the battery to the Batt side of the coil and the whole entire time I had the tach wire hook up to the distributor. That was the main problem. When the negative side of the coil stay grounded the coil will stay de-energized. Thank you for all your help and time. Sometimes it's better to hear second or third opinions. I hope it's all down hill from here ) .. Later all..

Hi Joe, Yes I was going to call you tomorrow morning. I called Pete Paraska today and a friend of mine locally. Unfortunately the local friend just got into a motorcycle accident so he couldn't come over to help. I just went over my garage with a fully charged battery jumper and cranked the car and still no sparks. I had enough of this thing and ready to pour some gas on it and light it up.. I just went over the car and found some interesting stuffs on this car. I will post the link here if you like to see. http://www.cardomain.com/ride/721840/3 Later guys I got one more thing to try and that is hook up everything to the distributor outside the car and try to spin it by hand. If that gives me sparks then the battery is definitely weak and not spinning the motor fast enough to generate enough AC volatage accross the pick up coil. Will let u guys know the result tonight and hope it will be good result.

I spent the whole day on the friggin Z and still couldn't get it to start. It's just a simple problem "no sparks". I replaced the ignition module then the coil and still no sparks. Then I put in a new distributor and I got sparks. I plugged everything back up and cranked it up. It started for a brief second or maybe 2 and shut off by itself. After that I got no sparks again. I spent the next few hours swapping parts with no luck. Then I double check the 2 wires at the coil and there it was the problem I cross the friggin wires. So I decided to go back to the auto parts store and get the new distributor, coil, ignition module, rotor and cap and went to diner and very sure that when I come back the friggin thing will start with everything new. Well after diner I put everything new in there and it still no sparks. Here is what I think the new problem: If the battery is weak and not spinning the rotor quick enough can it not get sparks because of that? Because when I turn it over the motor turns over fine but I measure the voltage accross the pickup coil and it was only .3 Volts AC. I took it out and spin it by hand and was able to get it up to like 1. something Volts AC. I am charging up the battery and will try it again tomorrow morning. Can someone tell me what type of voltages at each stage within the stupid distributor? After a day playing with the dumb distributor I think there is nothing special about this piece of $hit. Here is my theory how it works correct me if I am wrong. The pick up coil picks up small AC voltages that enters the "ignition module". When the ignition module sees the AC voltages it will send the grounded signal to the negative side of the coil. This will energize or de-energize the coil and send out the pulse to the spark plugs via the rotor. So if the AC signal is not big enough then it will not trigger the ignition module. Does anyone know what is the required voltage to trigger the ignition module? Also if it works the way I described then I can check the coil's function by momentarily ground the negative side of the coil while cranking I should get some kind of sparks coming out if the coil is OK.. Ok I am tired.. any info would be great guys.. I doubt I have time to get to the response until tomorrow night but please give me what your have guys.. Thanks

David, This is great news. I am sure you can sleep better at night now hehe.. When I bought my LS1 I got a chance to hear it ran so I am confidence that my motor is solid. Please let me know when you are ready to sell me the auto tranny. As soon as I get the tranny I will begin putting the motor into my Z. Look like I am not too far behind you and I will have to find time to come down to your place so I can learn all the tricks. Good luck.

This symptom sounds like a problem with the AFM (stock EFI) and MAF with the Z31 EFI. Next thing I suggest is to check your TPS also. Good luck..

EZ-E, It's not easy to take the first step. I give you a lot of credit for that. I 've been there so I know. I had to learn many things by just experimenting and the results were not pretty. Every thing takes times and practice. Good luck on your next project..

EZ-E, Congratulation.. How much did everything cost? I didn't see alot of couplings. I hope you have enough couplings for easy removal. I did my 3" Cat back pipe with JeffP's dp recently too. I could have helped you measuring all the bends especially the one over the rear Xmember. I added a coupling right after it coming down from the rear cross member so that you don't have to remove the driveshaft to take out the rear pipe. Good job though..

Listen to EZ-E.. Check the connection for the CAS. That's the signal that the ECU will use to give you sparks. Try to put in another turbo distributor.

525, I have 2 280ZXTs and they don't drive the same. My 81 280ZXT drives real good and the 5 speeds 79 converted turbo doesn't feel the same. Also I did a search and found your old post about how long does the car goes into close loop and my 81 does kicks into open loop and my 79 never. If the ECU doesn't use the speed sensor and the RPM then why these 2 sensor got feed back to the ECU?

What type of MBC are you using? The bleeder type or the ball & spring (hold boost and release) type?