k204drek Posted August 18, 2012 Share Posted August 18, 2012 I just got this car and was told it needed a tune-up but it has a brand new tune up just done to it. When we unplug the plug wire from plug 3 nothing changes. It runs good up until about 2k and after that the turbo starts to spool and the boost leaks really bad and it falls on it face. But when sitting in nuetral you can rev it up to about 4k and it will backfire and then go higher but it wont build boost in nuetral. I think one of the reasons it runs so bad is because it has bad gas in it, but i really don't know. I drive the car everyday and i drove it home going 65 on the interstate but it just wont get on it, and it takes about 3 or 4 miles to get up to 50mph. I need help asap because its the only thing i have to drive. Quote Link to comment Share on other sites More sharing options...
ArchetypeDatsun Posted August 18, 2012 Share Posted August 18, 2012 Try looking at all connections cleaning or changing battery terminals could help, clean up the ECU connection those are known to get corrostion as well as the harness. Mine is doing similar symptoms but mine is a total different problem. Putting new gas is always the first thing you wanna do especially If the car has been sitting for some time. That Lucas octane booster is good stuff I'm not s big fan of octane booster but that's the only one I'd buy. Quote Link to comment Share on other sites More sharing options...
ScumbagS130 Posted August 18, 2012 Share Posted August 18, 2012 (edited) I'm having the same problem. :/ Edited August 18, 2012 by ScumbagS130 Quote Link to comment Share on other sites More sharing options...
k204drek Posted August 18, 2012 Author Share Posted August 18, 2012 Ill try to make it into town today and get some octane booster. And let you know how that helps. Quote Link to comment Share on other sites More sharing options...
Ernest Harmon Posted August 18, 2012 Share Posted August 18, 2012 Think about your original post.After seeing that removing the wire from #3 and not seeing a change did you swap that plug wire with another one to see if the wire was the problem? If you did and still had the issue then it's not the wire.Put them back as they were.Next remove the plug look for fouling,improper gap or a cracked insulator and replace or regap as needed if fouled it will be more involved."the boost leaks very bad". Where is the boost leak?Is this a stock set up?I can tell you from personal experience with my 81 zxt they do not like any kind of leak in the intake system when completely stock.This includes vacuum leaks.Mine would not run right on anything but NGK plugs BPR6ES-11's.Don't expect the gap to be right out of the box they aren't they may be close but not close enough.If all of this is right check the turbo for excessive slop.If you can feel the shaft move up and down the turbo needs rebuilt.If you feel no slop take the cat off if it is still there and go for a spin if that solves the problem it is time for 1 of 2 things a new cat or a cat delete.I didn't have anyone to tell me this stuff in the beginning and had to trust the service manager and got took for a turbo and a cat when the cat was probably the issue all along.After that incident I read and learned as much as I could on the car and started doing my own work. Quote Link to comment Share on other sites More sharing options...
k204drek Posted August 20, 2012 Author Share Posted August 20, 2012 Ok i figured out that my #3 injector had a crimped on wire undone. So we plugged it back up and it ran pretty good, you still couldnt floor it. You have to hold it about 1/2 throttle till 3k rpms and then floor it and it wont go past 5k rpms no way no how in nuetral or in gear. I unbolted the cat a few minutes ago it ran like complete crap. I have no idea whats wrong with it. I also changed plug wires it didnt make a different. I did notice that with the cat unbolted it did make the miss go down alot. Is it possible that i am 180 degrees out of time. Or my valves arent adjusted right or i just have bad gas. I have no idea. It take like 20 minutes to warm the car up you crank it it dies and so on and so on and then you finally get it to idle (like it has a huge cam) and you try to drive it and it takes you 4 miles to get up to 30. It was running perfect earlier then it just decided to start running like crap again. Please help. Sorry if i repeated anyhting. Quote Link to comment Share on other sites More sharing options...
k204drek Posted August 20, 2012 Author Share Posted August 20, 2012 Think about your original post.After seeing that removing the wire from #3 and not seeing a change did you swap that plug wire with another one to see if the wire was the problem? If you did and still had the issue then it's not the wire.Put them back as they were.Next remove the plug look for fouling,improper gap or a cracked insulator and replace or regap as needed if fouled it will be more involved."the boost leaks very bad". Where is the boost leak?Is this a stock set up?I can tell you from personal experience with my 81 zxt they do not like any kind of leak in the intake system when completely stock.This includes vacuum leaks.Mine would not run right on anything but NGK plugs BPR6ES-11's.Don't expect the gap to be right out of the box they aren't they may be close but not close enough.If all of this is right check the turbo for excessive slop.If you can feel the shaft move up and down the turbo needs rebuilt.If you feel no slop take the cat off if it is still there and go for a spin if that solves the problem it is time for 1 of 2 things a new cat or a cat delete.I didn't have anyone to tell me this stuff in the beginning and had to trust the service manager and got took for a turbo and a cat when the cat was probably the issue all along.After that incident I read and learned as much as I could on the car and started doing my own work. I swapped the wire with another it didnt change anything. My spark plugs are gapped at 32 i also cleaned them it made a heck of a difference for a while then it started running like crap again. I already fixed the boost leak, It is all stock.The turbo is in good shape. I ubolted the cat and it didnt make a difference. Quote Link to comment Share on other sites More sharing options...
darkstarrocker Posted August 20, 2012 Share Posted August 20, 2012 Sounds like you have more than one bad vacuum leak. Replace all the vac and fuel hoses under the hood. Check the afm boot for cracks. What is your timing set to? Quote Link to comment Share on other sites More sharing options...
k204drek Posted August 20, 2012 Author Share Posted August 20, 2012 Sounds like you have more than one bad vacuum leak. Replace all the vac and fuel hoses under the hood. Check the afm boot for cracks. What is your timing set to? I will replace all my vaccuum hoses. I was thinking that the afm boot might be cracked ill check that also its just a pain to get to. I have no idea, Where are the timing marks on an l28et. Quote Link to comment Share on other sites More sharing options...
k204drek Posted August 20, 2012 Author Share Posted August 20, 2012 I adjusted the timing just by turning the distrubitor a little bit to accomadate for the lack of back pressure due to unbolted cat and it runs great in nuetral. You just touch the throttle and it goes to 3k. Then you hold it on the floor and it goes to 3 stops for 1/2 a second then spools up and goes to 6k and then i let off. Quote Link to comment Share on other sites More sharing options...
Ernest Harmon Posted August 21, 2012 Share Posted August 21, 2012 (edited) Lack of back pressure should not effect the timing.You need to set the timing with a light.The removal of the cat will let the turbo spool up faster due to no restriction to hold it back.Have you checked the tps for proper operation or the AFM? Edited August 21, 2012 by Ernest Harmon Quote Link to comment Share on other sites More sharing options...
k204drek Posted August 21, 2012 Author Share Posted August 21, 2012 Ok I had a cat put on it it was definatally part of the problem runs great but not perfect. Ok a new problem has arose, anything above 2k rpms all my gauge lights come on like when the key is in on position but not running. What is the tps supposed to be set at? Quote Link to comment Share on other sites More sharing options...
k204drek Posted August 22, 2012 Author Share Posted August 22, 2012 I believe i need to complete flush my fuel system i will start on that probally this weekend or sooner if it gets worse. It still takes forever to warm up which as i was read that the reason why it takes forever to warm is because the gummed up fuel system while cold is smaller and as it warms up the flow gets alot better. But after it warms up it runs great. It back fires while downshifting thorugh the intake and exhaust. It runs good enough to drive till i get the fuel system flushed. Quote Link to comment Share on other sites More sharing options...
Ernest Harmon Posted August 22, 2012 Share Posted August 22, 2012 You need to look here. http://www.xenons130.com/reference.html download the zip file for your car.The "TPS" Throttle position sensor varies its value based on where the throttle is positioned.As far as a fuel system flush some SeaFoam or a quart of NAPTHA "in the paint section at the hardware store" with a fill up will help.You may have a cold start valve issue also. Quote Link to comment Share on other sites More sharing options...
k204drek Posted August 23, 2012 Author Share Posted August 23, 2012 I have the FSM i havent looked it at to much. I have ran seafoam, lucas, 2 bottles of b12, gas treatment and ocatne boost I run 93 in it all the time. It has all made it a little better. While i had my key in the on position a few minutes ago i could here the fuel pump straining and squirting some thick stuff threw it so im going to clean the tank and blow through the lines and clean out the fuel rail. Quote Link to comment Share on other sites More sharing options...
Ernest Harmon Posted August 23, 2012 Share Posted August 23, 2012 Have you changed the fuel filter? While you have the tank out you might as well replace all of the fuel hoses with new to be on the safe side and for peace of mind. Quote Link to comment Share on other sites More sharing options...
k204drek Posted August 27, 2012 Author Share Posted August 27, 2012 Have you changed the fuel filter? While you have the tank out you might as well replace all of the fuel hoses with new to be on the safe side and for peace of mind. yes i changed the fuel filter. Its been running better and better each day. Quote Link to comment Share on other sites More sharing options...
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