First question of many ( will only start with easy start )

[jodylee4444]

Evening people, i have just been given a puma from my sister who was going to scrap it as it has very poor running. Its an R-reg 1.7 which i have recently done cam belt and water pump + thermostat, and has been running fine.
The problem is now it wont start with out easy start and ticks over at about 200 - 400 rpm and is misfiring but if you rev the engine its absolutely fine no mis at all and as soon as you let the revs drop its back to lumpy idle and misfire also if you hold the revs anywhere in the range it misfires i have had the codes read and nothing.
I have done a compression test and leak down test and was all ok, new plugs and leads, cleaned out the idle control valve, found a broken wire on the connector under the power steering pump fixed and still the same.
I hope some one can help and point me in the right direction.
could it be the map sensor at the back of the engine ?

CHEERES Jody

 

[xztraz]

Check electrical connections to engine.
Suspectable are Ground strap and give the battery terminal connectors a good clean and make sure they sit tight.

Check for vacuum leaks. (little rubber plug on the throttle housing often cracks)

Cleaning the maf (carefully) could be good.

Could be the coilpack.

No codes you say. hows the fuel mix on the engine? open loop/closed loop?

 

[oilburner]

I think you should get the engine re-timed, it's notoriously difficult to set the timing on a 1.7 without the correct tools

 

[mix2000]

Sounds like a vacuum leak
How better is it starting from hot?
Could be underdetecting at the temp sensor.

 

[martinthrapston]

Check icv as that controls your idle,if junked up clean with carb cleaner and then lightly oil the shaft with 3in1 oil,disconnect battery for a couple of hours whilst doing icv,this will reset ecu,reconnect,allow to idle on its own no throttle for about 20 mins,then take for a drive normally and driven like you stole it so as ecu can relearn new values etc,clean maf as suggested aswell .

 

[CherryVimto]

Also, there is no MAP sensor. The little square thing I think you are referring to is for fuel vapour recirculation. I'm pretty sure it has a fancy name which eludes me at this moment in time....

 

[jodylee4444]

Cheers for the quick replys, I will check the timing again tomorrow. But has been running for the past 4 months so can't see it being that but will check anyway as for electrics I'm not that good on but am good with mechanics. I have checked the vacuum pipes and all look ok. The icv which I have taken off and cleaned I powered it up and it only moved about 1/2 a cm ( should it move more that that ).

 

[oilburner]

It might be worth checking the coil packs too

 

[yippeekiay]

Just throwing this in there as smething to check as I can't remember if it could cause this issue.....clutch position switch above the clutch pedal, check it hasn't fallen off the bracket or become disconnected.

I could be way off but always remember this fix for some reason :lol:

 

[jodylee4444]

Right got a coil pack on order and will be this afternoon and have just checked the voltage on the TPS and on closed throttle its showing 4.7v and doesn't really change but i would of thought that it would read this at full throttle.
Does anyone have any experience with this ?
CHEERS Jody

 

[mix2000]

Not really sure, no doubt someone will correct me, but somewhere in the back of my head says 0ish to 5ish volts, 0 being closed and 5 being fully open. Regardless the voltage the value should change when moving from open to closed.

(Dunno why i stuck the voltmeter into the back of me head????) :shock:

 

[mix2000]

Found this on an old notepad;
"The TPS has three wires,
1 of the wires will have 0 volts this is the earth,
1 of the wires will have 5 volts this is the supply
and the other wire should have approx. 0.7 volts at idle
and increase to approx. 4.5 volts at full load "

[edit]As far as i remember it was for a 1.4 [/edit]

 

[xztraz]

if you have a obd reader. check throttle positioning over obd. then you check the cable in the same process. 15% ish on closed.

 

[jodylee4444]

Right a small update i think i might has solved it, I put the coil pack on and no difference just before i went home i decided to pull the connector of the pressure switch ( below power steering pump ) and the TPS and i could not believe it it fired up and ran smooth as it should so i put the pressure switch back on and still running put the TPS on and it died so i have got a TPS on order ( fingers crossed ) :grin: