galloguy05 Posted May 8, 2009 Share Posted May 8, 2009 well if you all were following my last post about getting my car, well i finally did. I had a friend drive it home for me yesterday and we just tinkered around it but didnt do anything really. All i did was take it around the corner and wash the engine bay and what not. the car was running strong yesterday with the exception of a bad battery. Now with that being said, this morning i get in the car and take off to go to a buddies house to do some real work on the car and problems arise. the car shudders violently when i hit 2500 rpm. I think thats because the engine basically loses power after 2500 almost like theres a rev limiter on the engine. Ive done a search and checked the tps and afm but the car still will not rev past 2200-2500. Im at a loss for things to check besides maybe the fuel pump? maybe its bad and cant keep up? maybe the altenator and battery are bad and cant keep enough spark to the engine after that high rpm? Any suggestions to get this thing on the road? Quote Link to comment Share on other sites More sharing options...
The love of JDM Posted May 8, 2009 Share Posted May 8, 2009 On 240sx's it does the same thing when the MAF goes out. Most likely thats the issue you're having as well. Quote Link to comment Share on other sites More sharing options...
galloguy05 Posted May 8, 2009 Author Share Posted May 8, 2009 now i searched here and the other thread said if I simply unplug the tps while the car is running and then rev it and the car revs normal then the problem is the tps. Can i do the same with the MAF just to see if thats it or does it have to be completely replaced in order to tell? Quote Link to comment Share on other sites More sharing options...
The love of JDM Posted May 8, 2009 Share Posted May 8, 2009 Unplugging the maf to test it is what to do, if it goes past 2500 then yes its bad. Check connections first, sometimes the plug wires get junked up if they look fine then you might be able to spray MAF cleaner in it, if that doesnt help then a replacement is in order. Quote Link to comment Share on other sites More sharing options...
galloguy05 Posted May 8, 2009 Author Share Posted May 8, 2009 alright i'm off to try that out. Thanks for the info. ill post back with the results Quote Link to comment Share on other sites More sharing options...
The love of JDM Posted May 8, 2009 Share Posted May 8, 2009 You're welcome, g/l and let us know Quote Link to comment Share on other sites More sharing options...
galloguy05 Posted May 8, 2009 Author Share Posted May 8, 2009 i disconnect the maf and all the car does is ilde but when i give it gas it sputters and dies. so im guessing the maf is good....what else should i check? Quote Link to comment Share on other sites More sharing options...
The love of JDM Posted May 8, 2009 Share Posted May 8, 2009 Of course, When you unplug the MAF its going to die when you rev it. Which means after that test, if its connected and then wont got past 2500 its the MAF Quote Link to comment Share on other sites More sharing options...
galloguy05 Posted May 8, 2009 Author Share Posted May 8, 2009 I found the problem. It was the tps after all. i unlpugged it to check it and dry it out and then plugged it back in and tried revving it and see if that was the problem and it wasnt. So i ruled out the tps. But as a dummy i forgot to just try revving it with the tps all the way unplugged and i did that and it revs perfectly and runs smooth with out the tps. Thanks for the help! Quote Link to comment Share on other sites More sharing options...
FlatBlack Posted May 8, 2009 Share Posted May 8, 2009 If that doesn't work, test your fuel pressure, you can get an inline gauge from AutoZone/Orielly's or wherever you shop. Just run it right after the fuel filter. I had a really rusty gas tank and went through about 5 fuel filters within a year, you might also check that while you check the fuel pressure. *edit* Didn't see your post while I was writing this. Glad you fixed it! Quote Link to comment Share on other sites More sharing options...
The love of JDM Posted May 8, 2009 Share Posted May 8, 2009 Glad you got it fixed Quote Link to comment Share on other sites More sharing options...
galloguy05 Posted May 9, 2009 Author Share Posted May 9, 2009 thanks. Yeah i just left it unplugged and it ran great! so i decided i would go through and replace the fuel lines because they were in pretty bad shape. One was so bad that they actually broke apart as i was loosening other lines. So i had bigflatblack come by and help out because we had planned on working on it anyways today. Turns out i had the wrong size line and now i have to wait til my next day off next week to put the correct fuel line on. Ill also be getting a new battery so i dont have to keep jumping it. Going to see if there is a draw on the battery too because the battery looks fairly new. heres a few pics just for funzies bigflatblacks car with mine another of the 2 cars Lunch of Champions Quote Link to comment Share on other sites More sharing options...
The love of JDM Posted May 9, 2009 Share Posted May 9, 2009 You're car looks like a micro machine!@! Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted May 9, 2009 Administrators Share Posted May 9, 2009 TPS! You get water in the connector of the TPS, that will create a VIOLENT rev limiter, shutting off all fuel instantly at 3200 RPM and turning it back on instantly at 2800 RPM! The car will buck violently between 2800-3200 RPM until the water is dried out of the TPS connector. I typically just remove the connector and blow it out with my mouth. Some of you can tackle this on one breath. No harm is done, doesn't affect the ECU or TPS other than expediting corrosion of the connectors due to being exposed to moisture. This exact scenario has been covered here and every other Z car forum ad-nauseam as almost anyone that has washed their factory Fuel Injected Z car, discovers. What takes place is the water shorts the idle circuit in the TPS so now the ECU thinks the throttle is closed. The ECU interprets a closed throttle and at higher RPM, shuts off the fuel injectors completely for emissions and to a smaller degree, mileage reasons. At any RPM above 3200, if you close the throttle, the injectors shut off completely delivering NO fuel to the engine, and then turns them back on at 2800 RPM. If you put a free flowing exhaust on the car, sometimes you can hear it kick back on with a distinct "pop" in the exhaust when it happens. Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted May 9, 2009 Administrators Share Posted May 9, 2009 On 240sx's it does the same thing when the MAF goes out. Most likely thats the issue you're having as well. FYI gang! Z cars didn't have a MAF sensor till '84 with the 300-ZX! So what applies to MAF EFI system does NOT directly apply to the early Z car EFI which utilizes and AFM! Quote Link to comment Share on other sites More sharing options...
The love of JDM Posted May 9, 2009 Share Posted May 9, 2009 Opps, AFM sorry Quote Link to comment Share on other sites More sharing options...
bigflatblack Posted May 10, 2009 Share Posted May 10, 2009 thanks. Yeah i just left it unplugged and it ran great! so i decided i would go through and replace the fuel lines because they were in pretty bad shape. One was so bad that they actually broke apart as i was loosening other lines. So i had bigflatblack come by and help out because we had planned on working on it anyways today. Turns out i had the wrong size line and now i have to wait til my next day off next week to put the correct fuel line on. Ill also be getting a new battery so i dont have to keep jumping it. Going to see if there is a draw on the battery too because the battery looks fairly new. heres a few pics just for funzies bigflatblacks car with mine another of the 2 cars Lunch of Champions look at that sexy comet....lol ur driveway makes it look all high lol....hit me up on ur day off and i will come help u again!! Quote Link to comment Share on other sites More sharing options...
Tennesseejed Posted May 10, 2009 Share Posted May 10, 2009 look at that sexy comet....lol ur driveway makes it look all high lol....hit me up on ur day off and i will come help u again!! http://www.youtube.com/watch?v=8iffDvXTcm8 Quote Link to comment Share on other sites More sharing options...
bigflatblack Posted May 10, 2009 Share Posted May 10, 2009 http://www.youtube.com/watch?v=8iffDvXTcm8 lmao great one lol:mrgreen: Quote Link to comment Share on other sites More sharing options...
galloguy05 Posted May 10, 2009 Author Share Posted May 10, 2009 I think we just found the theme song for bigflatblacks car!..haha. Since he says we have to cruise mine blasting journey in denim jackets he has to cruise his playing that song...lol...got a deal bigflatblack?...haha Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.