Loss Of Power On Acceleration

[tarquin]

How often would you it a 1/3 of a bottle in

David

[Gabriel81]

For me, once every 3-4 fill-ups. Planning to add a full dose, which for the IQ will mean basically a double one as the fuel tank is so small.

I also fill up with Shell V-Power Nitro+ every other visit to the petrol station so hopefully that will keep the plumbing clear...

[tarquin]

Lets hope so. I was the first person on here to have the mod done only because i did a lot of electronic mods to my iQ and have been very friendly with my dealer who knew about the problem and the bulletin notice so was first in. But always worth keeping it clean as the modified pipe arrangement is only meant to reduce it sooting up not eliminate it.

David

[Andre122]

Ok so having spent 14 months trying to find out what was causing a general lack of performance and general lack of acceleration with no engine codes to go by.  It turns out it was the Camshaft Position Sensor (right of engine near the main hose below the EGR Valve) the sensor costs about £20 delivered from Autodoc..  It was easy enough to get out but a swine to get back in had to use a little weapon to get it home.  Word of warning if you are going to do this warm up the engine first fully as there is a little bolt you have to undo I recommend soaking the bolt overnight with WD as I snapped the head of mine quite easily to be honest once you get the blighter in it's unlikely to easily come out but much easier if you don't snap off the bolt.

[IQ_Samuel]

Hi, 

Thanks for the heads up Andre122 - I have just ordered one for my little IQ. 

I was worried it may be the EGR. May still be, but I'll get this mapped out if it turns out to be the problem. 

Fancy putting an EGR valve on a petrol engine. They're supposed to be less complicated than diesels, this is why I got one... 

[Andre122]

Hi,

Regarding Toyota IQ accelerating at low speeds issue and general lack of power at times like up steep hills especially.  I Originally had a bad CAT & O2 sensor so replaced all of that which cleared the engine light but not the problem.  A mechanic had replaced my EGR valve but the EGR valve sits on this inlet manifold flange not sure of the right name, the flange basically feeds the EGR valve with pressured gases to enable the car to accelerate in different types of driving like pulling away from a standstill and rolling ect.  The flange has little paper clip size holls in the 3 ports for the 3 cylinders this is where the gases channel into the flange and into the EGR valve.  When I took mine off it was chocked with carbon so I think I have fixed the problem at last, I did a road test and it felt very different I will update this post on the outcome.

[Andre122]

Re above on the EGR flange issue.  I can confirm the car is now driving like another car it's amazing.  To clean the EGR flange or whatever it's called is not hard.  Wipers off, Scuttle plate off, Throttle body off,  undo the 3 EGR bolts, undo the 4 manifold bolts, undo the the 2 intake bolts/ undo the fuel rail or loosen it some ear cleaners a paper clip and a tin of EGR cleaner and reverse save £300 + or £600 if the garage decides to give you a new EGR valve.