Hello hope you are having a great day. I have had this issue on my MR2 since owning it: when engine has warmed up, there is a hesitation between pressing accelerator and engine responding. It is the worst when idling waiting at traffic lights, but also happens when cruising and want to accelerate. Sometimes, it hesitates and engine nearly stalls. The engine bogs down for 1 or 2 seconds, then revs climb normally.
Car has clocked 110k miles, year 2000.
Fixes tried so far:
1. changed exhaust manifold O2 sensors
2. new spark plugs + air filter
3. cleaned MAF sensor
Otherwise the car passes MOT fine, idles fairly smoothly when warm around 800 rpm. Now I have more time on my hands I would love to sort this issue out: any ideas? Thanks
I recommend getting an OBD dongle and dowloading Torque Pro to your phone. Then you can check what you sensors are doing.
It could well be a maf issue. They don't cause the check engine light to come on.
Quote from: Carolyn on November 5, 2025, 09:47It could well be a maf issue. They don't cause the check engine light to come on.
+1
Quote from: Carolyn on November 5, 2025, 09:47I recommend getting an OBD dongle and dowloading Torque Pro to your phone. Then you can check what you sensors are doing.
It could well be a maf issue. They don't cause the check engine light to come on.
The maf sensor live data looks normal, and has been recently cleaned. No other codes
@Dagnet Could it be just that the accelerator cable has stretched and/ or that the tick over speed is too low?
Neither of those things would explain it's only happening when it's warmed up.
It could be a leaky injector.
Quote from: Carolyn on November 5, 2025, 18:36Neither of those things would explain it's only happening when it's warmed up.
It could be a leaky injector.
Agreed!
I like your suggestion, it seems ( the amount of) fuel related to me