[Mk2] [Turbo] Urgent help needed

[Thethorne]

Right where to start..... Well I brought my mr2 turbo and on the way home typical I noticed a miss fire mid range I thought new ignition components would sort it so I've replaced the dizzy cap arm leads plugs and coil pack which made no difference. Over a period of 3 months the car got worse to the point it idles at 500rpm and has very little power if you hold your foot down in say 2nd or 3rd gear all you get is a sudden loss of power with lots of pops and bangs. So I decided to read my fault codes and I got 24 which is intake air temp sensor and 25 running lean. I replaced both the air temp sensor in the intake and also the one in the manifold with a genuine Toyota one costing £121 thinking this should solve the issue. But it hasn't. I've now got exactly the same problem except I now have code 23 as well as the others. I'm really not sure what to do now. The car is a Rev4 turbo with an arc intake berk exhaust with a decat any help would be great as the car is pretty much impossible to drive now. Thank you. Thethorne

[Ryan S]

have you got rid of the running lean code? Could be low fuel pressure caused by a 20 year old fuel pump

[Al-sw20]

Yep, check fuel pressure.

[mr2magic]

I'd check the iat sensor wiring first. Is the resistance at the ecu the same as at the sensor?

[Thethorne]

Hi and thanks all for the help I've checked the fule pressure and changed the fuel filter and no difference I will check the risistance at the Ecu is the same at the sensor I take it I just check the sensor wiring colours and follow them back to the Ecu.

[jimGTS]

Hi and thanks all for the help I've checked the fule pressure and changed the fuel filter and no difference I will check the risistance at the Ecu is the same at the sensor I take it I just check the sensor wiring colours and follow them back to the Ecu.

"checked fuel pressure", so what was it?


before just replacing sensors, did you actually check the old ones?? resistance etc via the manual? check wiring etc?

reading codes and just replacing sensors is not the way to diag issues.
the manual shows you how to check these are working, its only the last resort of replacing sensors.

[Thethorne]

Hi and thanks for the reply again the fule pressure read 35psi with the ignition on but not running and as for the sensor I replaced I can't remember the exact readings but the old one measured 1.? and the new one 2.? So I replaced it as I already bought it.

[bishop]

some fuel pressure at static doesn't necessarily mean you are getting correct fuel pressure under load. your pump maybe tired to the point where under idle or low speed conditions it supplies enough fuel but as soon as you ask more of it the flow rate is no longer enough.