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Bad throttle loom does not damage ecu. But bad engine loom will. Shorted maf wiring is usually the culprit. What are your fault codes? Usually u need to completely rebuild those throttle bodies.
ye did a full rebuild withe the throttle body !! but stiill the same symptoms !! how can i check the ECU ? please can you give me some tips !!
i feel the engine retards !! its misses but wont back fires at 2000 RPM when the throttle is pressed its stall the engine for sometime and with a backfire it start to increase RPm this is very irresponsive !! and the vvt solenoid has not signal from the ECU !!
i know it is the ECU but i cant swap it cause its a japan spec !! and this particular ECU is not available !!
Firstly if your car has an immobilizer with a red green lamp on interior mirror you cannot stop ecus as they are married to immo. U would need to make it virgin. If u have no immo. Then u can use any ecu from same year. Don't worry about Japan version. Secondly have you checked if you have power on vvt solenoid there should be 12v with ign on. I asked you about fault codes? Explain how u rebuilt the throttle body. Did you renew the brushes in the potentiometers? Did you service the motor? How can u be sure it's the ecu? The VVT not working will not cause your problem. To test vvt you must actuate with diagnostics tool. Your issue sounds
Like a bad maf, what are the maf output values? 12kg/h is the spec at idle engine at 80 deg AC=off
Rebuild engine loom too. If throttle loom was bad the rest will be bad too
no i dont have the red green lamp on interior mirror ! and yes checked the voltage to the VVT at ign it is 0 volts and no difference at idle or incresed RPM .
so here are the fault codes DTC
diagnosing on pin 4 at 38 pin connector
number of blinks of LED (analog diagnosing method since its 1994 ) the scanner didnt show nay readings
but as you can see the actuator shaft is welded so we cant remove it but i managed to rewire it successfully
and i checked the motor alsoo it works with a dc 5 v
well i have replaced the MAf from the company itself !! can that alsoo be causing problems and i didnt check the maf outputs how can i test it ? your advice might help a bit more for me to dig up the problem
and i checked the engine wiring loom also nothing seems to be the degraded !! i check the connection with a multi meter
and also i crossed cheeked each and every line with diagrams that i took from the WIS.
the wiring loom is okay as feel !!
U need to clear those faults first and then recheck what comes back!
Star diagnoses or any scan tool will be able to read live data from that ecu.
So if u don't have 12v on cam solenoid check in wis where Power comes from and what fuse. I can assure you power does not come from ecu.
Usually I machine the welding off and strip the TB completely to rebuild it!
I am afraidnu need a scan tool. It's going to make your diagnoses much easier. That way u can see maf values and Throttle body angles. U also need to learn the throttle end stop values with the tool. DO NOT MESS INSIDE THE ECU! not until you have properly diagnosed all inputs correctly. Measuring wire resistance does not always help. You must measure what the ecu sees that is voltage levels.
So step 1, clear faults run the engine recheck what comes back.
If that does not help. Get hold of a scan tool
Good luck
thanks friend and what scan tool would you prefer !! and where can i find the
replacement potentiometer for the TB and leads ? i have a obd2 snanner but not a xentry
im not sure whether my model will show live data !! will it ?
i cleared the faults grounding the pin 4 clears all the codes but again it comes back !!
and in the TB if u strip off the welds how are u re welding it !! doesnt it miss align !!
Any decent scanner will read live data. And yes your ecu supports live data, actuation, and coding. HHT is the genuine MB tool if u could get your hand on that you will be sorted. I watched that you tube video. That guy does a half job. Also there is no need to grind that washer off to lift the gear. That pin can be knocked out complete from the underside. There is an access hole from the rear. I do machine off both levers for potentiometers. Brushes u find only from another used TB. I reweld it with a Tig welder. Not an easy job. You need to power the potentiometer and adjust output voltage before u weld. It needs to be spot on.. to the mv. or TB will not program.
How is the loom between TB and ecu? Cut it open to see. Maybe source a second hand TB to test with. I have repaired hundreds of these looms and TBs and really you need the scan tools to make a proper fix
that loom is also i good shape !! unfortunately my friend in my country parts are very expensive !! i tested every thing i made a cut but ill further see if have some damaged wires ! but as i feel this is a improper ignition timing !! i feel the engine is retarted !! back fires a hell lot !! wel im using OBD 2 scanner ! unfortunately it didnt show nay codes so thats why i tested it with the manual method !!
Very strange u get no codes but u get codes with impulse method.. Your backfire or popping sound in intake is typical of a lean mixture. Check fuel pressure also! The only way ignition timing can be out is if u have damaged segments on the flywheel. Only way to test that is with a scope on the crank sensor input. Make sure u have a clean signal
yes !! very strange !! well i tested the crank sensor too !! it give 0.6 volts of AC signal !! i replaced it too !! but for a physical damage to happen i didnt run the vehicle that rough i did my maintenance well !! and i replaced the fuel pressure regulator , fuel pump , fuel filter too !! and i check the voltage at the fuel pump it pumps continuously while it runs the engine and its 14 to 12 volts
and im afraid that its a kinda of a huge back fire ! and it blew off the intake plastic cover also and replaced it too !!
Voltage check on cps means nothing. Scope test only. As a start. If u happy with maf and its genuine MB or Bosch. Then cut the maf plug open and rewire it to the ecu. Is there power at the maf?
Voltage check on cps means nothing. Scope test only. As a start. If u happy with maf and its genuine MB or Bosch. Then cut the maf plug open and rewire it to the ecu. Is there power at the maf?
so friend what do u suggest me to do first !! cause i have checked all what u said expect for the scope test on the CPS but its a new one !!
and the TB i didnt check it completely as u said !!
Ok then maf is good! Let's start with fuel pressure? I know u replaced it all. Even better disconnect return line back to tank start the car and measure quantity back to tank. You should have around 1L in 30-40sec
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c200 1994 is it HMF or PMS
