Testing eha valve with multimeter mercedes benz The amp test for the EHA valve is like this. The mechanic (reputable) quoted me $400 for a new one. Naturally, automotive-related tools will be used. Reading the duty cycle from a digital meter (DMM) is straightforward. Primary coil Read a few threads and most complained about EHA valve leaking fuel. The EHA is built specifically for modifying control pressure in accordance to the KE lambda O2 system. To actually test this one must view What I'm getting at here is that the only valid readings to take relevant to the EHA are those of current. Once you undo the electrical connector and remove the two screws holding the EHA to the dist (watch for the fuel spritz) you can pull it off. For unknown reasons (maybe to soak up pressure pulses), it has a short length (~2" of this hard plastic, black rubber-coated) hose. Sent from my EVA-L19 using Tapatalk The slotted screw you see on the mating face of the EHA valve is not an adjustment. Last week I noticed a fuel smell coming in through the vents. Quick visual inspection lead to me find leaking EHA. It may be time to whip out the old multimeter if you ask me. A 1989 300E w124 with 67k miles. The EHA valve is only used on We really need to install an ammeter inline with the EHA wires to check the current. 0 auto 1989 euro spec. I replaced the valve and O rings (all cleaned first!). Was so lean the exhaust smelled rotten eggs. The car previously had LPG instaled which has been deleted since. I would recommend a fuel gauge or two and a multimeter or two for the best diagnosis and setting the oxygen fuel mixture after you get the EHA adjusted to run the best. The EHA valve is only used on vehicles with the KE-JETRONIC fuel injection system. Adjusted the EHA so the engine run ok without ECU. Readings should be 12 volts with A/C compressor on and zero volts with A/C compressor off. The So I have a small gas leak that seems to be coming from the EHA valve. 2019 White Audi Q5 - 35k 2016 BMW 535i - 38k BenzWorld. So I put my multimeter in between one of the connectors of the EHA (tried both) to the according plug connection and the other wire from eha to plug connection directly. Since portions of the test involve a running engine, you must exercise extreme caution when working near moving parts. ). I swapped the ECU and EHA valve too, but that didn't make any change. As tjyak50 pointed out, they fit in the two recessed fuel ports on the actual fuel distributor itself. Did not make a change in any of the other operations. org forum is one of the largest Mercedes-Benz owner websites offering the most comprehensive collection of Mercedes-Benz information anywhere in the world. An EHA current measurement loom-insert will be made. Had to enrichen the new EHA way over half a turn just not to fry my cats. Car is working normally. The EHA valve controls fuel enrichment/adjustment pretty much everywhere. Bosch EHA is mounted on the fuel distributor but the 2 pins female electrical connector not connected to the EHA. org forum is one of the largest Mercedes-Benz owner websites offering the most comprehensive collection of Mercedes-Benz information Leaking EHA valve. org forum is one of the largest Mercedes-Benz owner websites offering the most comprehensive collection of its funny you mention the eha,ive been having the same issues with mine,i replaced the old one with a used one off ebay,had the air fuel ration recalibrated,i found the engine runs like crap boggs ,loss of power,pops in plenum,needs to warm up to operating temp. k. Primary coil terminals: #1 (-) and #15 (+). Hello, I have a 190e 2. Therefore, it is important to find a reputable and trustworthy Mercedes specialist who can properly assess and diagnose EHA valve problems. After much speculation, I went ahead and tore out the fuel distributor (old diaphragm had multiple needle holes in it), ordered a rebuild kit, put the distributor through ultrasonic cleaning, changed out the 6 metering o-rings, cleaned the barrel filter, regreased the 2. Please take a few minutes to complete your profile. Replaced a leaky EHA in January with undetected air leaks in the rubber boot. Fuel pressures also seem o. 4 Bar system/LC delta because with a new/ untouched EHA a 0+/- current indicates a . Testing for problems with the EHA valve requires specialized knowledge and equipment for working with Mercedes vehicles. "You have chosen to drive a MERCEDES-BENZ, a car in whose construction and production we have taken great pains because we believe that quality is not a matter of chance. Testing is simple by measuring the resistence between both pins. This provides the duty cycle that the fuel injection ECU is using when it controls the EHA valve. To actually test this one must view system and lower chamber pressure. 19 and gound. Optimize your fuel delivery with the Bosch Fuel Injection Electro Hydraulic Actuator/EHA Valve F026T03002. The idle control valve is located in-line with the bypass hose which is connected to the throttle valve plate. This EHA Valve has a DC Resistance of 19. Any ideas/suggestions on how to solve this problem will be greatly appreciated. I am not getting any current reading either on ignition Im an electrician by trade and know there is a way to check lamda control by the second smaller diagnostic port by front driver side. While troubleshooting bad cold starts with abs light on my problem with that was resolved with new coolant temp sensor, lambda (was probably still original) OVP, ICV(was stuck), new alternator, all the vaccum hoses to the ICV and now EHA which was Fuel pressure test and multimeter test the EHA next on the cards. org forum is one of the largest Mercedes-Benz owner websites For the test procedure you will need (and know how to use) a decent multimeter with voltage, resistance, and amperage measuring functions. Sears has a very . Not the fitting to the left. Is leaving the EHA valve unpluged causing any sort of damage to the fuel distributor or engine? At some point you will need to resolve this issue and some diagnostic testing will be required. you can smell it when you open hood . Using multimeter, test input voltage at ECU between terminal No. Sure enough it is my EHA valve. Is this a way to test EHA? No gas leaks by The EHA valve itself reacts to varying current flow by causing the programmed leak within to grow and fall. I have not yet measured continuity between the switches in the engine and the CIS. See attached table what the resistance should be at a certain temperature. I purchased my first Mercedes. BenzWorld. You I also noticed prior to this that the EHA (electro-hydraulic actuator) was leaking, and I showed the mechanic. I tested the oxygen sensor and it generates 800 MV, so it passes the test. " Just got my new EHA valve Mercedes W124 1989 230E engine M102 recently purchased. I recently joined benzworld. Obviously the EHA is having an affect on the running so it seems to be working. I do not see the leak from the top however I see it drips once a minute or so. If reading is incorrect on either test, repair short in circuit. This fuel distributor pressure regulator fits a wide range of Mercedes models, including 560SL, 190E, 300E, 560SEL, 420SEL, and more. I understand that the voltage varies according to the inputs (I would guess; engine temperature, potentiometer, position of the air plate, O2 sensor, etc. I am not getting any current reading either on ignition When I turned the multimeter off, it dropped to about 50%. The site includes MB Forums, News, Galleries, Publications I daily drive the Best Thing Mercedes-Benz made at its Best Era: 🙌 The W140 S600 V12 (I think) Use a multimeter to test coil primary resistance at coil terminals. In later models with KE-Jetronic like the 560SL, there is a valve called the EHA valve that replaces not only the "frequency valve" but also the WUR. As for the transmission holding gear; bowden cable may be a tad too tight. During all this testing the EHA valve started to leak in the body. I have a big leak at my EHA valve on the side of the distributor. org forum is one of the largest Mercedes-Benz owner websites offering the most comprehensive collection of Mercedes-Benz information Hello everybody, I acquired a 190E close to a year ago, and have always had problems with it idling. A new fuel-test pressure kit is on the way from the States. Hi bsclifton: The EHA (Electro-Hydraulic-Actuator) is an electrical valve that controls the pressure on the CIS fuel distributor. I took the valve off, did not see any cracks. org forum is one of the largest Mercedes-Benz owner websites offering the most comprehensive collection of Mercedes-Benz As I understand if your EHA has not been played with the EHA current in lambda will give you a clue as how close you are to an ideal . The valve consists of two opposed windings, an armature and a rotary slide. So you need to make up a set of test leads that will let you connect your In this 13-minute CIS training video, Kent will walk you through the steps recommended by Mercedes Benz to fully test the operation of the EHA valve on 1984 to 1993 4, 6, and 8-cylinder engines with KE-jetronic fuel injection. In this 13-minute CIS training video, Kent will walk you through the steps recommended by Mercedes Benz to fully test the operation of the EHA valve on 1984 to 1993 4, 6, and 8-cylinder engines with KE-jetronic fuel injection. then when i disconnect the eha,the car runs strong has lots of power,does not The idle control valve keeps the idle speed stable under various engine operating conditions. Drop it in and test it. If reading is correct, test is complete. 1. Plus - EHA valve adjustment (under the blanking plug, on For me, fuel leaks from the bottom of the EHA valve but also starts seeping at the TOP of the EHA valve where it meets the side of the fuel distributor. I am assuming that purpose of EHA is to provide extra fuel needed for starting and during the initial engine warm up Hello all, My name is Christian and I am a young mechanic working for a repair shop. 1 Ohm which is OK Manual states 20 Ohmcurrent of 15mA as shown here once running is OK per Megawatt Man from MBworld when it leak , it get wet . Also swapped the idle speed control relay from the 420SE just incase it pairs to the ECU better, The 500SEL was idling at 500rpm which is low but I don't remember it low like that before so it could be the 420 tuning on the 500. So what is the purpose of the EHA. The duty cycle of the EHA valve is determined by the O2 sensor. Disconnect EHA connector and install harness adapter for current testing, Harness adapter is available from Mercedes Benz. The site includes MB Forums This EHA Valve has a DC Resistance of 19. I discovered that my EHA valve is leaking (somewhat choppy, idle, hard hot start, and fuel smell). The face of the EHA that's against the fuel dist, has a couple of holes in between the attachment screws' holes. There are several things that can go wrong with the EHA valve, and depending on what I would like to know if someone has a prodecure that I could carry out with a multimeter to test the EHA on my 1987 560 SL. 1 Ohm which is OK Manual states 20 Ohm210mV Voltage as shown here once running is OK per Megawatt Man from MBworldI The frequency valve is on a 380SL; it's function is replaced on a 560SL (sort of) by the EHA valve. 4B delta You should make up a harness to test EHA current See link here beginning at about 4 mins for way to construct the harness. More current more fuel passing. I've checked the EHA wires for continuity, measured the resistance, checked the resistance trimming plug, and everything seems to be fine. The o-rings do NOT go around the torx bolts. Reactions: BenzWorld. It's on the LH side of the fuel distributor, connected to it by two convoluted metal lines. The site includes MB Forums Testing as done in the article verifies control! The EHA valve itself reacts to varying current flow by causing the programmed leak within to grow and fall. Seems to work fine except the leak. He inspected it and told me that it has a crack and needs to be According to the web page maintained by Mercedes owner in Japan, he have disassembled several broken EHA's and found that there are two valve settings, one is 6 and 1/2 turns back from the end, and another is 5 and 3/4 turns. Throttle Valve Switch Set multimeter to read highest ohm scale. Jump to Latest The true test will be when I park the car outside overnight and trying to start it in the morning. so usually , the Yup, to replicate the 4 pin coolant sensor when testing fuel differential pressure and adjusting EHA. May I ask why I may not unplug the eha? I did test the fuel pressure regulator and it is working. if you have a pressure leak , it goes to zero in a short time . to diagnose this issue , connect a pressure gauge at the end of cold start valve [ assume you dont have the right one ] crank car , pressure is around 75 psi , with engine off it drop to around 40 , and stay there for some time . The O2 sensor must be warmed up to provide good info and then the computer goes "closed loop" which just means that it is using the O2 sensor info to control fuel delivery. electro hydraulic actuator or EHA valve is an integral part of the Bosch KE-Jetronic fuel injection Wife's '87 W124 230E has had the EHA valve diagnosed as leaking. I replaced O-rings first, which did nothing. Make sure the two O-rings that seal the EHA to the dist aren't lost. abpn hxus uklaanw guelp rgnrggx rftwpwl lfaxcz ptrc qqsu bovuiw