Captain_Fantastic Posted March 3, 2009 Report Share Posted March 3, 2009 Ok guys i really really need your help. I have a ke70 with a 4k. it has over sized pistons, ice ignition dizzy, large cam, a 32/36 webber and it is balanced. lately it has been having an issue which is causing it to... do stuff. i can't explain it. Every now and again it will suddenly die in the ass. Like when you run out of fuel it will jerk along. It is always at completely random revs/speeds and sometimes it doesn't happen at all. some times if you back off the throttle for a bit it will stop and you can drive along without stopping. other times its a lot more violent to the point that it almost feels like its gunna break something, and you have to pull over. You can wait for a bit then drive off as if nothing happen. everyone who has been in the car believes that it feels like it is running out of fuel. It has been happening more and more frequently. I figured the fuel pump must be on the way out, so i installed an electric fuel pump. This didn't help the problem at all and now it wont even idle. If you turn it on it will go from about 50 rpm(no joke, each time it feels like it actually has died) back up to 1000 then back down. I have no idea what could be happening and this is my only mode of transportation. i realise i havnt explained myself very clearly so please feel free to ask more questions but i reallly need to be able to fix this in the next day or so. Help me rollaclub, your my only hope. Quote Link to comment Share on other sites More sharing options...
kiahn Posted March 3, 2009 Report Share Posted March 3, 2009 mine does the same, i thort my engine was gonna rip itself off the car it was shaking so much :dance: my car is fully stock apart from exhaust and k&n air filter. ive asked heaps of people i know about it and they said its fuel or ignition (or both) replace the spark leads and coil and check engine timing ive gone through 3 bottles of carby cleaner in a month and it seems to be behaving a little better, also if you feel it starting to shudder pull your choke all the way on and drive like that until you feel its safe again this is what ive been doing whenever i start to feel the idle drop and small shudders and it goes away within 30 seconds i still have no idea what it could be, so I'm getting a 4age instead and just driving it cautiously until then hope this is of help to you, Quote Link to comment Share on other sites More sharing options...
Captain_Fantastic Posted March 3, 2009 Author Report Share Posted March 3, 2009 mine does the same, i thort my engine was gonna rip itself off the car it was shaking so much :dance: my car is fully stock apart from exhaust and k&n air filter. ive asked heaps of people i know about it and they said its fuel or ignition (or both) replace the spark leads and coil and check engine timing ive gone through 3 bottles of carby cleaner in a month and it seems to be behaving a little better, also if you feel it starting to shudder pull your choke all the way on and drive like that until you feel its safe again this is what ive been doing whenever i start to feel the idle drop and small shudders and it goes away within 30 seconds i still have no idea what it could be, so I'm getting a 4age instead and just driving it cautiously until then hope this is of help to you, yeah i have noticed that if i douse the outside of the carby in wd40 or rp7 it runns much better for a very short time. everyone has told me so far that it is fuel or ignition or both aswell. but i tryed the electric fuel pump and i have replaced the coil twice. still happens :dance: i can't afford to go 4age this is shit. sigh Quote Link to comment Share on other sites More sharing options...
kangaroosa Posted March 3, 2009 Report Share Posted March 3, 2009 Have you tried blowing compressed air through the fuel line? Years ago my fuel line was chock a block full of gritty sand. It blocked the fuel line and only allowed minimal fuel into the carby. You would be driving along and then all of a sudden it would start jerking and surging. Much like you, if i backed off or even clutched in it would allow the fuel to build up in the float bowl and give me enough time to pull over. Quote Link to comment Share on other sites More sharing options...
Captain_Fantastic Posted March 3, 2009 Author Report Share Posted March 3, 2009 which fuel line? do you mean from the tank to the engine or from the filter to the engine? the same problem was experianced with this engine in another corolla. so i believe that the problem is to do with things attached to the engine. like the fuel pump or the catby or the leads or somthing i am going to replace the spark plugs and leads and see if this makes a difference. then take the fuel pump and the carby to a specialist. Quote Link to comment Share on other sites More sharing options...
kiahn Posted March 3, 2009 Report Share Posted March 3, 2009 which fuel line? do you mean from the tank to the engine or from the filter to the engine? the same problem was experianced with this engine in another corolla. so i believe that the problem is to do with things attached to the engine. like the fuel pump or the catby or the leads or somthing i am going to replace the spark plugs and leads and see if this makes a difference. then take the fuel pump and the carby to a specialist. I'm not sure it would be your carbies coz mine has stock carbies and still has the problem.. do you have the original spark leads or some newish ones?? Quote Link to comment Share on other sites More sharing options...
luke.t. Posted March 3, 2009 Report Share Posted March 3, 2009 hay mate check your fuel lines anyway you may have shit in the fuel tank(it is 20 odd years old).... also check you have no air leaks from your inlet manifold..... maybe get your carby re-jetted/tuned may have blockage..... just a suggestion but this is what i would do and have done before to solve a similar peoblem hope all goes well Quote Link to comment Share on other sites More sharing options...
Ella Posted March 3, 2009 Report Share Posted March 3, 2009 hey guys... to give some background this is my old engine, i sold the car and it was written off, jack has put the motor in his car. the engines a very grumpy 4k-c when i had it the issue only effected the car when flogging the shit out of it, like during a burnout its suddenly die or if you give it through the gears by the time the revs come on in 3rd it dies in the ass yes it feels like a ignition miss or a fuel float level problem but i never really bothered to fix it i thought a tune of the carby (which is almost brand new before i got the car, untuned) would fix it well the tuner couldnt replicate my problem on the dyno, but he installed new air corrector jets, said the rest were fine oh and it made 56KW atw :| oh the engine itself is getting long in the tooth, and i reckon jacks been giving it a caining. its a seven year old motor (since it was built) and regularly gets pushed above 7000rpm too. dunno if any of this helps or not. lol Luke. Quote Link to comment Share on other sites More sharing options...
Captain_Fantastic Posted March 4, 2009 Author Report Share Posted March 4, 2009 The problem has only recently come back and it is doing it randomly not when flogging it. it didn't come back while i was doing a burnout or anything either. i don't think the way it gets driven is directly the cause of the problem. i took it to a mechanic and he told me that it has a vacuum leak around the throttle shaft on the carby. but he also said that it would only bother it at idle. thinking about putting a standard carby back on and seeing if it has the same problem. after i change the leads and the plugs. to answer kiahn it has newish leads not the stock o ones Quote Link to comment Share on other sites More sharing options...
Gentleman. Posted March 4, 2009 Report Share Posted March 4, 2009 i had the same problem all i did was pull the carby apart give it a good clean and put back together it hasn't done it since. Quote Link to comment Share on other sites More sharing options...
trav_555 Posted March 4, 2009 Report Share Posted March 4, 2009 yea id say carby or vacuum leak, maybe upgrade to twin carbies with a real good tune? that would fix both those possible causes i would say or save up and get some efi even :| but my 4k does it too, its getting hard to start cold now :D so looks like I'm gonna have to change carby as i just did and it got worse Cheers Travis Quote Link to comment Share on other sites More sharing options...
Captain_Fantastic Posted March 4, 2009 Author Report Share Posted March 4, 2009 standard carby goes back on tomorrow. i was talking to someone today and they said that if the fuel line is too close to the engine, (since its a flexible hose to the carby not the original copper line) that the fuel might be boiling in the line? and the spluttering is when you goe only spurts of fuel going into the bowl. and that once the revs drop for whatever reason and the line cools a little bit, the fuel pump can regain the pressure and then its all fine? Quote Link to comment Share on other sites More sharing options...
Redwarf Posted March 4, 2009 Report Share Posted March 4, 2009 Sounds pretty much what I was going to suggest actually. I've only read this for the first time tonight, and my thought as I was going down the page was fuel vaporisation. I had it with my SU's. Fixed by a heat shield between the carb and exhaust, and some stuff called Stratoflex over the fuel line in the hot area. Any sort of heat shield will do. The first one I used was the rego plate off my car trailer. When that worked, I made one of exhaust gasket sandwiched between two thin pieces of stainless. Look also at where you fuel line is routed and see if any changes to that will help as well. Let us know how it goes. Quote Link to comment Share on other sites More sharing options...
coln72 Posted March 4, 2009 Report Share Posted March 4, 2009 I was going to say the opposite. I think that the carby is icing up when you are under constant throttle and is choking itself of air. When you stop it melts the ice and the problem disappears. When it does it, fell the carby to see if it feels cold. My old ke35 used to do this on the freeway (3kb'd 5k). It would start to miss and carry on and if I kept driving it would get to a stage where it wouldn't run under 4000rpm. Would be driving along the freeway in third revving the shit out of it. Weather didn't have to be cold for it to do it either, used to happen in the middle of summer. Fixed it by fitting an air hose that picked up from near the extractors. If I knew I was going on a long drive at constant speed I would also add a small amount of octane booster as well. Quote Link to comment Share on other sites More sharing options...
Redwarf Posted March 4, 2009 Report Share Posted March 4, 2009 It just goes to show where we each live, Col. Ice?? What the hell is that?? :| Quote Link to comment Share on other sites More sharing options...
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