explorer Posted April 21, 2011 Share Posted April 21, 2011 (edited) Hey...just wondering if anyone here migh have had this problem with starting/idleing revs with a injection manta? a month ago i had a drive which was about 4/300miles..it ticked over at 1000 after 10 minutes ish...i noticed she was ticking over at 12 or 1300 revs about 2 hours into the journey....then a few small drives later for a week or so-she wud tick over at 1500revs when fully warm....all these journeys -she was still driving without fault in every other way,water temp normal,oil level perfect..... than anoth long drive,about 250 miles.....when warm and for all of the journey- she wud tick over at 1500 or 1600....it didnt notice any performance issues-prob a little thirsty thou!.... then parked it for a week...sat in and took it for a 20 mile spin to test it.....the car started fine,reved to 2200 then 2500 and stayed there..i though after warming up,it might idle at lower revs-it didnt....all the 20 miles-she never tiicked over at less than 2500...stopped her and started her-same again-at 2500.....during this spin-this is the first time i noticed that she wasnt happy if i put the accelrator FULLY to the floor-there was a sound difference (at the latter end)as pushing pedal to floor-she gave a dead choking sound like she getting flooded just at the point of the pedal from 3/4 to full accelration to the floor...while i heard the choking sound-there was very little/no actual accelration..... ...... if i only half pushed the accelrator-it sounded fine and drove fine and accelrated fine......i parked it at a garage then....i left it for a week..... she then refused to start,she would try to turn over and wouldnt get there(starter and battery are fine)-i could smell petrol so presumabely it got flooded...if i tried starting with a little trottle-it was worse...sounded flooded quicker...... ...i changed the sparks in her,they were wet from all the petrol/flooding or whatever and fairly sooty.......with my new sparks in,i opened the ring clip on the engine side of the airflow meter and i removed the steel housing carrying the airflow meter and k and n filter(fairly new) etc.....so now that 3" diamater rubber pipe from engine was now open to air-she car started after about 30 seconds of turning over.....she stayed going fine...ticking over at 1000 ish maybe 1100 etc...if at any stage i put the steel housing(with airflow meter and filter)back into the 3" rubber pipe,she wud just start to rev up to 2500 again....she wud sound flooded again under heavy accelration while airflow meter in place.....it reved better with airflow meter not in place......if i put my hand here where the airflow meter wud be connected-it wud try to suck it in.... the little door inside the metal under the airflow meter is working normal (door swingin in and out etc)and freely with the spring acting as i think it should... any ideas about it??!...do i need to buy a 2nd hand working airflow meter and a tps thing???or can these be fixed /tested to find out if mine are faulty?mine might be working perfect-and it may be somethng else but i dont know..thanks..good luck... Edited April 21, 2011 by explorer Quote Link to comment Share on other sites More sharing options...
mantadoc Posted April 21, 2011 Share Posted April 21, 2011 When it is idling fast pinch flat the hose going to the auxiliary air valve. The hose I mean, if you are not familiar with the parts name is described below There is a large rubber elbow from the Air Flow Meter (thing the filter is in) to the throttle body (on the manifold that has the butterfly in) Half way along this a pipe as thick as a finger "Tees off" and goes to something (auxiliary air valve)near the thermostat housing. Squash it flat when car is warm and idling high. If idle returns to normal the auxiliary air valve needs cleaning / fixing / replacing The auxilisry air valve lets more air in when cold via the tee. It idles OK with the elbow off because the AFM is closed and it is held too lean. Once you fit the elbow the extra air going into the plenum (inlet manifold) causes the AFM to open a bit, car thinks throttle is pressed and adds more fuel and it loops in that cycle until if finds balance depending on the amount the valve is stuck open. The TPS is a crude switch. Car will run fine with it disconnected so disconnect if you like to eliminate. All it does is tell car throttle is closed (goes lean at idle) or throttle is wide (maximum enrichment) any throttle opening in between it just works it out from AFM and REVS / TEMP Other major cause of overfuelling is a faulty thermo time switch. eliminate this as a cause if the pinching the pipe flat does not work by disconnecting the cold start injector on the back of the flenum chamber. It's the blue one. Careful of the clips as these get brittle with age. You could possibly have two problems with the unexplained flooding, i.e. auxuliary air valve and the thermo time switch Quote Link to comment Share on other sites More sharing options...
explorer Posted April 25, 2011 Author Share Posted April 25, 2011 sound out mantadoc....im home on wed and thur and ill give that a go.....i located three 2nd hand parts for her, airflow meter,tps and a auxilary air valve off a engine that was running fine..... so i was advised to change 1 at a time starting with auxilary air valve then airflow meter then tps........ill try what u said before i change anything...thanks for the detailed diagnosis information.....ill let ye know how it works out Quote Link to comment Share on other sites More sharing options...
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