91 190E not starting
 

Hello every one, I have a question about the position sensors. I ran a few checks, first was the spark, It has good spark, then the fuel, it has fuel at primer and at cranking. Has any one had trouble with a position sensor when both these items are good? :eek:

jnt:

2.3 or 2.6 engine?
Do you have spark at the coil lead, but not at the plugs?
Distributor cap & rotor OK? Rotor turning?

Since the fuel system is K-jet there is no need for a cam signal, and the ignition timing is signaled by the crank pickup, the cam position sensor may be an additional input used for spark timing, or is redundant.

Frank thank you for your reply, the spark is good at the plugs that's the end I checked with my spark tester. and we have good fuel flow the only thing I was thinking was spark timing. this unit has a sensor at the front of engine as well as the rear. thank you Frank for your reply.

Just to narrow it down for sure, take off the air filter housing and give a few quick bursts of starting fluid. Just because there is fuel at the main fuel line does not mean it's reaching the injectors....also, could maybe be the opposite, make sure the plugs aren't soaked.

Hi Ismalley, I did check the fuel at the top of the injector and it was weak though when the flapper was pressed it increased the flow. The plugs are not wet

The last guy I helped with this issue had a disconnected ICV vacuum hose at the intake boot location.
Have you verified the vacuum hoses going from the intake boot to the bottom of the ICV, and also the top vacuum hoses at the ICV?

well I have check the idle controll vale, in fact one of the first things inspected

new update on this non starting proublems we tryed to use eather and still it failed to ignite.

I agree with this. If it's a 2.3 there's a main vacuum hose going to the bottom of the intake that does become disconnected and will cause a no start even with good spark and fuel delivery.

Did you check your Crankshaft Position Sensor (CPS)?

Ohms?
Cranking voltage, ac?

Just a thought: did you check your battery voltage? What about the OVP? If that is good, what I would do is go back to the beginning....What I mean by that is start from the throttle body and work your way up. You've already established fuel and good spark, so the problem will most likely be found between the throttle body and the injectors unless the O2 sensor causes a no start, which I doubt. So take everything off down to the manifold where the throttle body sits. This will give you a nice bird's eye view of things, it will also allow you to check the integrity of the integral parts of the air components. To get everything off including the throttle body is roughly a 15 min job so it isn't bad at all. But before you begin I would make sure you have a set of various size o- rings, some carb cleaner, gasket material (autozone sells the gasket material, the rubber/paper for the throttle body housing), a couple feet rubber hose for vacuum connectors, and also the IACV hoses. The IACV hose is the only specific thing that you need to order. These other parts are necessary so that you can replace the o-rings on the nylon injector guides, various vacuum tubing since everything is off, the throttle body gasket. Tools you need to complete this job is: 10mm socket for the nuts on air cleaner and nuts securing the wiring harness and fuel distributor; 17mm wrench for main fuel line and return hose; 14mm wrench + 5/8 inch wrench (14mm for the fuel injector lines, 5/8 to fit around the metal guide so the injector doesn't turn); 12mm wrench for the cold start valve; 5mm hex for the bolts holding in the injectors and for the bolts on the throttle body; Phillips screw driver to undo the clamp fastening the rubber boot on the fuel distributor and to undo the TPS attached to the manifold (not the throttle body). From here you can bench test injectors, and check the integrity of everything. Also you can now see into the manifold and see if there is oil pooling inside, which would mean worn valve stem seals. Note: you do not need to remove the IACV to get the fuel distributor off, you only need to disconnect the hose on the right from the IACV. If your hoses are good, then you don't need to replace them. I know it seems like a lot, but I can literally have my throttle body and all the above mentioned components off the car ( 2.6L) in 15 minutes. Good luck.

Did you spray starting fluid on the air filter as suggested in post #4? Better yet I would depress the air intake plate and spray the fluid into the chamber. Before starting, just for giggles, unscrew the gas cap, release the vacuum, and screw it back on. At this point, try to start the car. If the car does start you might be looking at a fuel delivery issue.

Hello every one just to let you know I replaced the crank shaft sensor but to no avail.
still will not fire, so I am thinking about the sensor at the front crank shaft .

starting fluid
 

ar
yes so i bought rear crank shaft sensor sprayed again still no start.

Did you check the voltage of the battery and test the ovp? You should try properly diagnosing the problem before buying the parts

Like I said in a earlier comment, did you check the main vacuum hose under the intake? If you have good spark and you have fuel, either by delivery or priming it and it won't fire, a massive vacuum leak will cause this. Is this a 2.3?

voltage
 

the bat is at 13.2

voltage and vacuum
 

2.6 vacuum ok

How did you check the bottom vacuum hose? Did you remove it along with the plastic nipple to check the condition?
Are the spark plugs wet after trying to start the engine?

no fuel
 

after some free time today I pulled the no.2 injector an caped it with a water bottle(16oz) just because some one will ask.lol I had checked the pumps and ovp and was getting strong fuel flow and pump are working at prime and run setting. but when I checked the injector no fuel. I do not understand why I had no start up with starting fluid but I did not. I had Larry rebuild this fuel distributor last year, so I am at a loss as to the trouble.

Did you try lightly pressing down on the fuel distributor plate?

Well, if you have spark and you introduce fuel directly into the intake, bypassing the fuel management, it should fire. Unless you have no compression or a vac leak. Simple rule. Fuel, spark, compression and air, but not too much air and the engine will run. Maybe you should run a comp test. For something like this you need to start with the basics before guessing and throwing any parts at it. These 103s are pretty simple engines....Are you sure you're getting nice blue spark? Can you hear a nice tapping spark if you hold the plug suppressor just off the tip of the plug while cranking. Are you checking your spark at the plugs or at the coil? This has got to be something very simple. Check to see if your bridge at the end of the cam is broken to see if the rotor is spinning. they do break sometimes and will have spark off the coil, but it won't
make it to the plugs.........I'm really curious now..

You didn't mention this in the first post, but did your engine stop and not re-start while driving, or would it not start after sitting?

Ok folks i have finely recaptured my fuel test kit low and behold 3.4 bars and .4 bars so I ether have a badly contaminated fuel filter or bad pump. have another project so this will be on hold for today

check first purchase last
 

So ok I bought the position sensor but it did not fire with the eather so I jumped to the conclusion that it was electrical. I did not have my fuel testing equipment, so all I did was check to see if the pumps worked.

I recently had a similar problem on my 190E 2.6. Testing and analysis pointed to the fuel accumulator. I tested it by disconnecting and plugging the hose on the backside that tees back into the supply hose from the tank and installing a test hose on the accumulator nipple.

Turning the ignition on energizes the fuel pumps for a second and when I did, fuel ran out the test hose indicating the accumulator had failed internally and was not holding pressure. So when the fuel pumps are energized, fuel is shorted back into the supply hose from the tank and the system will not build pressure. A friend with an '82 911SC had a similar problem a couple of years ago, and it was the accumulator.

Now, here's the rub. There is no available stock of the Bosch replacement part, 0 438 170 035, and Bosch USA does not expect to have any until the end of May. Mercedes does have stock, 000 476 06 21, and the list price, $287, is about double the price of the Bosch part from Pelican.

I did find an online dealer in Kansas City who offered the part for $190 plus shipping, but they had to order it from the Fontana warehouse. So it goes from Fontana to KC and back to me in SoCal. I hope to have the part by the end of next week.

Suggest you run the same test on your accumulator and go from there. The same acculuator was used on virtually all models with four and six-cylinder CIS-E engines from '84 to '93. I'm really suprised that Bosch ran out of this part in the USA. It may be the most common CIS part failure.

Duke

duke 2.6 I have a list of testing, after my fuel gauges got back to me my first test showed 3.4 bars .4 bars, so two new fuel pumps later I have 5.4 bars and 5 bars good to go still no fire in the hole. still more testing I took my spark plug tester to see how the spark looked, low and behold only one spark I then checked each spark plug and the same thing one spark only. As if it had a bad ballastresister so now I am looking at coil or ezl though I am going back to check the accumulator. but for now I am looking for answers and opinions.