4K missing.

[pervert]

I have a problem where my 4K has a bad miss.

This is a problem that happens maybe 4 or 5 times (sometimes more), in a 10 minute drive, and is a sudden miss, sometimes by itself, and sometimes in a series of 3-10 odd times...

I'm just looking for anyone to suggest any possible things to check, the following is what has already been checked/adjusted/replaced if possible;

Carb, fuel pump, plugs, points, leads, HV lead, fuel filter, distributor cap, coil pack, coil/distrib connections, timing, and I'm sure others that I can't remember...

Thanks.

[DVLRCR]

did you check your vacum advance? maybe that has something stuck in it thats making it move around...?

just something else to check... havent had this problem myself

[Big pun]

I had a simular problem with my old 4k..
took me ages to figure it out, the leads seemed fine but then I put on a spare set I had & took it for a drive, problem solved.

so if you haven't already, replace the leads

[fuel]

Did you check the gap on the spark plugs? Should be 0.7~0.8mm.

[rollas22]

Had the same problem on my 4k in my Starlet Sprint, would be fine on cold start up and drive, once got a little warm would miss... so replaced the plugs and leads and it was fine.
Check the temp range of the plugs? could be using the wrong plugs maybe

[overcast]

Plugs for a 4k should be BP5ES (ngk or equivilent)

[vvega]

hha check the points again
if they have pitting replace the condensor on the side of the dizzy

v

[pervert]

hha check the points again
if they have pitting replace the condensor on the side of the dizzy

v

Pretty sure we got that sorted, it's got new points with the dwell set right...

This mismatched spark plug idea is a good one, I'll have to check that!

[Virtual Genocide]

Plugs for a 4k should be BP5ES (ngk or equivilent)

Are you sure?
If the engine's standard he should be using the larger electrode verisons. Which is what toyota specify. The BP5EA-L or the BRE527Y IIRC
In saying that i use the BPR5EY in my 4k, but it has higher compersion etc etc

Pervert: Have you done a compresion or leakdown test latley? Might be a good idea to check everything inside is sweet.

Phil

[Vertigo]

yep, i recently had this on my 2A. try the condensor, leads, and ignition coil.

[Jebus]

Electronic ignition would make all these troubles go away

[Virtual Genocide]

Electronic ignition would make all these troubles go away

Not another one.

Waste of time if you want reliability IMO
Electronic ignition on the 4k (etc) has a tendency to blow the ignitor. Not to mention the advance curve *shudder*

[Ae92typeX]

youve done points, but have you replaced the condersor?

[Vertigo]

btw, it will get REALLY bad if you ignore it. eventually it would jutter and stall in unfortunate places. and then not start.

[pervert]

btw, it will get REALLY bad if you ignore it. eventually it would jutter and stall in unfortunate places. and then not start.

Haha, funny you should say that!!!

That happened last night on the way home, took ages to start again...

So you suggested condenser, leads, and ignition coil?

[Jebus]

Electronic ignition would make all these troubles go away

Not another one.

Waste of time if you want reliability IMO
Electronic ignition on the 4k (etc) has a tendency to blow the ignitor. Not to mention the advance curve *shudder*

Oh ok, havnt had any problems with it in the past ive found it to be superb had a 5K running electronic and didnt ever give me a single fault.

Also Pervert my girlfriends 2A was doing exactly what yours is doing, it got to the point where it cut out at intersections, wouldnt start, had no power etc. We replaced the dizzy with one from a 4A (electronic with internal coils) and it ran perfect ever since, and had more power than other 2A's ive experienced. On hers we replaced EVERYTHING similar to what youre doing, but nothing seemed to fix it until we went to electronic ign.

[Vertigo]

i must remember that.

[overcast]

Plugs for a 4k should be BP5ES (ngk or equivilent)

Are you sure?
If the engine's standard he should be using the larger electrode verisons. Which is what toyota specify. The BP5EA-L or the BRE527Y IIRC
In saying that i use the BPR5EY in my 4k, but it has higher compersion etc etc

Yes I am sure, I just finished my job of 3 years at a Automotive Parts Distrubitor in CHCH and I owned a high compression 4K till about 2 weeks ago.

There is little differnece between a BP5EA-L and BP5ES and I havent found one place that actually sells a BP5EA-L plug.

Check the leads, dist cap, condensor, plugs, also mite be worth replacing the fuel filter and clean the carb.

[pervert]

Check the leads, dist cap, condensor, plugs, also mite be worth replacing the fuel filter and clean the carb.

Done all of those things multiple times, replaced the condenser yesterday with no improvement...

[Vertigo]

its probably a combination of the things i mentioned, knowing electrical parts.