Fuel problem? Maybe? Help!!

[sirsprinter]

I own a 5K KE55, and last night at 85% full throttle into a 4th gear corner, I backed off and negotiated through, and noticed the car start to cough and shudder as if it were choking, or misfiring or it was starved, and proceeded to spit and cough and carry on until stalling.
It wont hold a steady idle, revs up and down and carries on quite roughly, and cuts out.

First thought was a fuel problem, so I got it going and limped it home. Where it would violently shudder and spit and cough until ¾ throttle where it would appear fine and purr away?

Upon limping home I first checked the fuel flow as I run an external elec pump. All good. Lots of pressure. So I by passed the fuel filter incase it were clogged, but all good. So I checked the coil leads and all the spark plugs. Clean and working perfectly. I checked the rotor button, contacts and cleaned and checked the points. All good. Secondaries are opening and its getting plenty of fuel.
Car still starts rough, revs up and down if foot kept on throttle, and upon letting go stalls?? Strange…

I proceeded to dismantle the webber after checking ALL vacuum hoses, and with the help of a mate, we dismantled and cleaned the webber completely and meticulously, and reset the float level, checked all the jets, and replaced the gaskets and reassembled the webber nice and tightly to no avail. Same thing. Cough and spit and carry on until high rev/load, therefore no difference!

So we checked the vacuum on the brake booster, as we heard sometimes it stuffs things around. All good. We are still scratching our heads and yawning as its 3am by this stage

Now we are completely dumb founded as what the heck is going on with the lil beast, as we pretty much double checked everything again this afternoon, where, when we drive slowly it carries on, but under heavy throttle/load it purrs like normal??

Any suggestions or advice?

Cheers

[oldcorollas]

it would violently shudder and spit and cough until ¾ throttle where it would appear fine and purr away?

with the help of a mate, we dismantled and cleaned the webber completely and meticulously, and reset the float level, checked all the jets, and replaced the gaskets and reassembled the webber nice and tightly to no avail. Same thing. Cough and spit and carry on until high rev/load, therefore no difference!

that symptom (on stock corolla carbs) is caused by something blocking the primary main jet. i have had it happen a few times.
car barely idles, then basically cuts out until you give 1/2 to 3/4 throttle and then ti kinda works... this is cos there is enough fuel being thrown in by the secondary jet to make car run (and also may indicate you have a very rich mixture at full throttle )

i would suggest you pull webber (normal downdraught type? 32/36?) down again, and use fishing line etc (thick stuff?) to poke thru the fuel lines on the primary side... poke from the throat back toward the fuel bowl.

alternatively, get some WD40/RP7 type stuff that has long thin tube for spraying, and sprays backwards thru all the holes (not just the main ones, but the progression holes too)

i think it is definitely fuel problem, and definitely in the carb..

good luck!

[sirsprinter]

BUMP

any other suggestions? when my mate comes over later today, we'll strip it down again and see how we go... and yer its a straight down 32/36 webber. Anyone had similar problems like this?

it just seemed weird to 'happen' at almost full throttle and back off, and yet when i return to similar load/rev its purrs like normal

cheers guys

[oldcorollas]

carb isn't sealed with silicon is it?

[Dazza]

I would say it is a blocked primary main jet because i had the same problem with my Hilux and that is what the problem was. I run a 32/36 DGAV Weber also.