(T) HELP! Punto 60 won't rev past 4k!

As title, my punto 60 won't rev over 4- 4.5k

It was misfiring so I changed the HT leads which has made it smooth but still wont go over 4-4.5k

Any ideas?

Ta

any warning lights on the dash?

Could be several things but try the old looking under the bonnet with engine on when its dark - look for blue sparks. Could be plug problem or coil issue.

Could also be collapsed CAT or silencer in exhaust.

Thanks for the reply. No warning lights on dash!

the manifold is blowing at the join to the downpipe... would that make a difference? Would a blocked CAT cause the engine to not rev up tho?

I could try a cheapo coil from work (ECP)

Ta again

if the CAT starts disintegrating inside then yes it can block up the exhaust and that limits the flow and thus power. same goes for the internals on silencers, not particularly common problem but has happen to me twice in the last decade. It blowing will not help but shouldn't make it not rev past a certain speed.

Ok ta for info.

Someone has suggested a dirty/damaged throttle body could be a problem or a faulty crank sensor.

I know how to clean the carb bit, but where is the crank sensor on these?

ta, Ian

Crank sensor is on timing side of engine, at about 3 'o'clock to the bottom alternator pulley.

While I've heard of faulty sheilding on TDC sensors causing a hard rev cut, I've yet to experience it on a FIRE engine (or a T5 ).

Can you rev the engine higher the 4.5K when the car is not moving, i.e. not in gear?

If I feather the throttle and then plant my foot at bout 3k sometimes it will push to 5k but its like its hitting the limiter!

I would say if you can not rev to the limiter without load is quite likely the ECU is running in limp mode. But usually this is accompanied by the warning light staying on. Make sure the warning light bulb is working first. You should see the warning light on when you turn the ignition on. If you don't the bulb is dead or disconnected and you don't know what is happening. I will be surprised a blocked cat will stop reving to redline without load but is still possible I suppose. Is your car defenetelly a MK1 Punto?

Not sure that Mk1 even has limp home mode!

Of course (I forgot) replace the fuel filter.

the cat failing can do that, somewhere or other i have the bit from inside my dads old cat, it had broken down into what can only be described as an egg shape and at certain revs it was pushed back into the exit of the CAT blocking it, engine could slowly push past this point if you kept your foot planted but didn't like it.

I remember almost exactly the same thing happened to one of the cinq turbo's on here, was a while back when martin owned a yellow one but its not really been on the forum for a long time now.

Eklipze3k's sei is doing this exact thing atm, gets stuck at 3k and i'm pretty sure its a blocked silencer on there (no CAT fitted).

I'm not sayiing its defo the problem but it could be and i have seen it more than once.

Are you getting like a buurrrrrrrr noise or is it just normal high rev sound around 4 rpm?

UPDATE

car cut out total loss off power. Won't restart had to push it to a garage where its sat outside at mo. Will give you an update as soon as i know anything.

Thanks for your input so far guys.

While it's sat there doing nowt, check for spark and pop the top of the air filter off so you can see down the throttle body while someone else cranks it.

If no spark and no fuel, the crank sensor is kaput.

Right.

both coils changed, new leads, plugs, fuel filter and crank sensor

runs now but still wont rev up and is drinking fuel.

Mechanic reckons it's something to do with the cylinder head and his diagnosis was scrapyard!