Guys,
this is starting to get to me,
i have replaed cap and button, new ignition coil all toyota genuine parts, and had just had iridium plugs 3 months ago, and my car everynow and then wont push me back in my seat stomping on it in 2nd gear doing about 4000 rpm, i have no vaccum leaks,
clutch was replaced with exedy hd clutch 2500kms ago, new timing belt, timing is spot on, and fring 10degrees before top dead centre,
ALOT of seals have been replaced, it has good compression 175 over all 4.
apart from that its a bone stock 1992 3sge aus mr2

sometimes ill stomp on it itll rip hard sometimes even break traction, and other times it will kind of stumble, not miss exactly but seems as tho is has no power then all of a sudden pick up a bit but no where near as hard as other times,

all these tests are carried out once engine is at op temp, and in the dry.


also, my horn has stopped working, relay was replaced, no dice still :(
it clicks, getting contact at horn, but no beep beep,
is there a fuse somewhere? and where is it located? i cant find it.
and if anyone has a spare horn id like to buy it

thanks guys

Have you replaced the Ig leads or tested them? Why was the coil replaced? was it bad?

Leads, have no been replaced the contacts still look good,
cap and button were fairly used and alot of whit powder in the cap,

coil was replaced as i was refreshing the entire ignition system, due to the car haven done 170kms on original parts still standard leads in there
but i have tried a few aftermarket leads, but cannot fin any that are small enough to fit into the dizzy cap, there all to large and dont go into the contact points properly,
and i dont really want to pay 220$ for standard leads, even at my buy prices, i still think its a bit steep, so ive been hunting for a suitable aftermarket replacement thats cheap and fit properly!


im thinking maybe ill pull th plugs check them,
and perhaps replace the fuel filter, havnt done that yet.. and i read that could have something to do with it,
or maybe the igniter, but dont really want to shell out another 150$ for another ignition part that may not fix my problem..
ill double check the timing and advance it a bit,
but my previous mr2 Na did not have this problem, so im trying to work out what was different in that one, and te timing was advanced.. but i doubt thats my problem.

:) just looking at the ends of the leads does not prove they are any good. It's the resistance and continuity that matters here.
If you are refreshing all your ig parts the leads should be right up there to replace way before a coil.
Just buy a set of the Denso ones from twosrus. Heaps cheaper than OEM.

I'd almost put money on the leads being the problem. I've replaced a couple of sets in the past due to similar problems that your experiencing. It's a lot more prominent on a turbo engine when the leads go bad.

Anyway that's my 2c on the issue.

I'm not sure why you want to advance the timing again though??? The engine works best at the factory settings.

Just checked Ebay and you can get a set of Eagle leads for about $100. Denso ones from Twosrus are about $50 plus post.
 
What cap and coil are you using? the ones with the large hole (90/91/92) or small (93+)?

Using
Genuine cap an rotor for my car so a 92 cap

And just got a set of topgun leads that fit properly

A lot better but still does it :( argh
So I'm thinking ill change the fuel filter that's pretty cheap

Then ill put some platinum plugs in cheaper then iridiums
And see what happens

If this dosnt work I'm gonna be stumped

I guess it could be a failing tps but I thought it would throw an engine light an code

:(


Anyone know where the horn fuse is
Or have a spare horn I can buy?

When your saying hesitation, how much slower are we talking?
Does the car barely move or does it just feel a bit slower then on other days?

Try resetting the ecu and see if that does anything. I think u pull the ecu fuse for 15mins.

have you checked fuel regulator, fuel pressure etc?