98 Corolla, Idle dies on cold start

dnme

Colleagues

You may be able to advise me on this, and if so I'd be very grateful.
I have a 1998 Corolla 1.3l. Its a grand car apart from cold starts. When I start it cold, it idles very low, so low that it cuts out if I dont keep reving it. After it warms up its fine. Once warmed the idle increases.

I'm wondering where to start with the investigation? Not great with cars so if you can - be gentle.

Many thanks

Muckie

Could ba any number of faults causing this problem.
Engine temp sesor, MAF no longer working. Maybe the trottle
body might need cleaning. Also check for breaks/cracks along any vacum lines. If theses are all good maybe a diagnostic check might be in order
€50 or less and at least you'll know the exact problem then.

dnme

Muckie wrote: »

Could ba any number of faults causing this problem.
Engine temp sesor, MAF no longer working. Maybe the trottle
body might need cleaning. Also check for breaks/cracks along any vacum lines. If theses are all good maybe a diagnostic check might be in order
€50 or less and at least you'll know the exact problem then.

Hi Muckie

What does MAF stand for?

Would you mind me asking, perhaps you could highlight on the photo . . .

1. Where is engine temp sensor?
2. where is the throttle body?
3. Wherer are the vacuum lines

Very grateful if you can help

MunsterCycling

gt112 wrote: »

Hi Muckie

What does MAF stand for?

Would you mind me asking, perhaps you could highlight on the photo . . .

1. Where is engine temp sensor?
2. where is the throttle body?
3. Wherer are the vacuum lines

Very grateful if you can help

http://en.wikipedia.org/wiki/Mass_flow_sensor

rsj

I had the same problem a few years ago - turned out the guy i'd bought it from had adjusted the idle revs so it would pass NCT on emissions. Think it was as simple as loosening/tightening screw to bring idle revs up. I will point out i have no mechanical knowlege myself, so this info may be useless.

dnme

rsj wrote: »

I had the same problem a few years ago - turned out the guy i'd bought it from had adjusted the idle revs so it would pass NCT on emissions. Think it was as simple as loosening/tightening screw to bring idle revs up. I will point out i have no mechanical knowlege myself, so this info may be useless.

when it warms up, it idles fine, infact it seems to idle a bit too high when warm

Muckie

Heres a pic of the MAF on a Corolla, your's should look something
similar.
Its the "thin back box" connected to the air intake housing unit. If this is disconnected and the car runs better, its at fault.
Sorry i don't have a pic of the Engine temp sensor, there usually down at the back of the engine(sound very much like yours is at fault, there not expensive either).
The vacum lines are connected to the trottle body(thin black pipes)
Check for any loose or cracked. Hope i helped. But still ask a friendly mechanic before you attempt anything.

dnme

Muckie

Many thanks, very much appreciated, I will go to my mechanic but am keen to learn a little myself as well.

rsj

gt112 wrote: »

when it warms up, it idles fine, infact it seems to idle a bit too high when warm

Exactly same as mine, but i'd go with Muckie's advice, he actually sounds like he knows what he's talking about.

Muckie

No worries lads, live and learn i say. None of us were born experts.
Hope you get it sorted. Keep us updated.

Muckie

No worries lads, live and learn i say. None of us were born experts.
Hope you get it sorted. Keep us updated.

PADRAIC.M

also the idle body could be catching the rotar, have probably repaired 5 of these in the last 12 months, bring it to a mechanic who is familiar with toyota's and you should be fine.

Flesh Gorden

Could be the Idle control valve too -It gets clogged with dirt over time and will give very erratic idleing

just had to clean one out for a friend the other day -
his car on startup would jump to 3k on its own then stay around 1500 mark and sometimes crash to under 500

cleaned it out with a can of Wynn's Carb/Inlet clener I picked up for less then€10

I sprayed it through the MAF, Inlet hose and on the throttle body aswell

it now sits perfectly at around 800rpm

a 20min job, In his car could only be accessed from underneath as it was tucked away near the inlet manifold


apart from that your spark leads could be at fault too,
cracked leads delivering a poor spark will cause a lot of other things to struggle on startup
if you haven't had your plugs and leads checked or changed in a long time it's a good place to start

cian1500ww

Thermostat could be stuck open taking the car longer to heat up.