corolla#123

For those interested the blue connection is to the idle up mechanism which helps adjust the idle

Thanks for the quick reply If the blue one on the front is the air temp sensor what is the on on the back of the airbox ? (I thought that looked like the temp sensor as it is long and prong like)

Can some one please tell me what the blue sensor on the front of the airbox shown on picture is and what it is for ? When warm the car suffers from a misfire as though the one cyclinder is not firing, its not regular and clears after the throttle is floored. Disconnecting this sensor clears the problem but I am not sure what effect this has on the ecu etc. (As the car fires and runs normally after disconnect the process such as sparkies and injectors must all function okay) It also clears after i disconnect the throttle sensor which leads me to suspect that disconnecting may force the ecu to a base map as opposed to the sensor itself being the problem. Error codes I get are 21 - Oxygen Sensor Signal 24 - Intake Air temp sensor 31 - Air Flow Meter - not sure about this as I have a MAP 41 - Throttle Position Sensor Am thinking that I will need to change some or all of these sensors but it would help if I knew what the blue one did !

Problem as I understand it is when the engine gets properly warm there is a bit of misfire at low throttle, but when floored it clears. It also has an exhaust pop after heavy throttle back off and the mixture is a bit rich. Although it sounds like a electrical sensor or ecu malfunction it is more likely to be the injectors are dripping into the cylinders, it happens more when the engine bay is hot. When on the freeway or travelling at speed the airflow disapates the heat and so the problem is less evident but in traffic esp stop and go the heat builds up and makes the problem much worse. The dripping causes the chambers to flood to a point where the plug can't create the necessary boom, it doesn't happen every cycle which explains why its not timing or tuning (given the std ecu does give you flexibility in fuel delivery it can't be that either). It misses at part throttle because it has no air, and therefore can't combust whereas at full throttle there is sufficent air. If you drive lots of short distances or a large proportion of long distances you can find the problem is barely noticeable and when you send it to the garage they fix something and viola you think thats gone too. Get your injectors serviced ie stripped and reset up with new seals etc with anything else do one thing at a time so you know what solves the problem !

I read in another forum of a guy putting a 264 inlet and 256 exhaust cam, does this make sense or is it overthinking ?

Does anyone know what a Haltech Interceptor will and will not do with a std 4AGE ecu, I am getting conflicting comments and as I don't really know much about them I hope some wise bod here does. I am told by 1 person that the Interceptor will allow fuel and ignition mapping to be adjusted through the rev range to suit and can cope with upgraded cam without losing driveability on road. However I am told by another person that this is all true for most other factory ECU's but the corolla one is a little less flexible and a full ecu is really required. I only want to add a slightly better camshaft and lightened flywheel and tune it to the best it can be as I am restricted by class regs and the requirement for it to be a road car.

Also won't help when it happens again out of warranty, replacing everything electrical is a lot of different possibilities :wink:

Thanks I was sure I had read most of the pages but obviously not LOL

Hey Guys Have a 91 Corolla GTI with a small port 4AGE 16v. I want to add a performance cam to it and am wondering if anyone has any suggestions as to the better supplier, I have found camtech & crow have listed cams for it any suggestions or comments. Is there a limit to valve lift ? What are the std cam figures for duration & lift etc Thx in advance