While driving engine shuts off

I replaced the 6-cylinder one for a 4-cylinder one. Nothing changed and I got depressed as in every unsuccessful attempt, the engine returned back to the hard starting and intermittent stalling but at a much less rate. A friend of mine suggested seeing an electrician that he trusts. I went there and he suggested that a temp switch that is responsible for cold starting is the prime suspect. That brass switch located right beneath the brake and ABS assembly ( hard to reach) had two wires of its harness worn out with their copper strands touching each other. He parted them a bit, a solution that can be further perfected tomorrow, I will replace the switch and isolate its wires from each other. Seems like rust never sleeps with me! Yet it is a progress considering the vague diagnosis in absence of scanner and working OBD DLC. I drove it back home ( some 25 km) and it looked like healed but I have to avoid over-optimism this time and allow for some 2 weeks time to make sure it is over this time.

Hi dear Danny. Upon dismantling the whole dashboard block last week I came across this blue monster, any idea what it is and what does it control? It came right to the left side of the steering column.

No my dear, I took a pic for the side that carries some marking, the other side is blank. My electrician said it doesn't look like the cause of my problem, and to support his POV he extracted it out and operated the engine. In fact, nothing changed, the engine worked as usual and stalled as usual too. You can drop this thread as long as it had never been an issue for earlier customers/members. I thought that as long as I have gone as deep as dismantling the whole dashboard then I would better seize this opportunity and give an idea of what I had found therein.

Meanwhile, I am trying another thing replacing the TPS. The exhaust fumes had been very irksome lately and I remembered that I had replaced the original TPS with a Chinese one that looks the same but with no defining code or number, it is used for Opel engines here. The first few minutes after switching back to the original TPS had the (Check Engine) warning lamp off this time and the exhaust smell is not that detested like before. Tomorrow will be seeing a prolonged test and I will revert back here with new news.

I told you, you are just great ! Unfortunately, I found this email of yours in the Spam folder, lucky I was to check SPAM folder while expecting an email from a new friend, one that hadn't arrived as expected. Thanks to you dear Danny.

Great thing that you had sent regarding the coolant temperature sensor, especially the pic that states how it can affect the PCM signal to fuel system. I tried my best so far, but due to the chaos that had been made with the 4 relays that are located in a pocket like enclosure right above the front right mud guard, I need your help to let me know which task does every relay have and what is the original part number of each of them, can you please? They were once all (Potter & Brumfield) brand, one for the engine coolant radiator fan, another for the A/C system, one for the fuel pump, the fourth is vague to me. Now after several attempts from my car mechanic the engine is still experiencing those sudden blackouts (which I will try dealing with that coolant temperature sensor) but I need to retain the default pattern of the 4 relays, what are their part Number. I know of the attached ones only, the rest in my car had been replaced by Korean makes 2 years ago.

Another relay I had a choice of only one image to load, unlike with your answers to me with multiple pics attached.

Those were the relays I have as spare parts: The forthcoming 4 images are for what I have right now, two of them are hard to read as you can see. I believe that my problems come from these relays (some of them).

Second image:

Third Image:

Fourth Image:

What is meant be "seated but not stripped"? Is it about the wire to never be stripped?

One more question please. Regarding this diagram which rang an alternate bell. The illustrated (Fuel Pump Switch/Oil Pressure Sender/Switch) had been giving me a hard time once, the fuel pump would fail to operate but one electrician did cut off one of the three wires attached to the socket of this switch/sender unit, most probably he had an earlier experience with it in the Oldsmobile Cutlass Sierra that had been used in Iraq in lots 2 decades ago. Every time I be replacing the faulty unit there is no response as per the oil pressure gauge, it just shoots at full reading. Lately I bought a brand new one, a bit longer than the original but to my surprise, it still does not give a reading of oil pressure. The car spares dealer blamed it on the instrument panel but I believe that the pressure switch is for a different automobile (Chevrolet or else). Any idea of how to locate the proper switch before buying it? Should it have a marking for pressure or a code may be? Where should its 3 wires go? Anyone to the ECM as your description on the diagram suggests?

Thanks for clarifying re the " Not Stripped" term, a new info to me. As for the pressure switch (which is referred to in your schematic diagram as being also a fuel pump switch because as I will be clarifying in the next few lines; it shuts the fuel pump every time the oil pump is not delivering enough oil pressure, a means of protection for the whole engine), there is some ambiguity here since my pressure switch has 3 wires, one of them is a brown one, the connector itself has 3 pins( female)! That electrician mentioned in my latest comment did severe the brown wire and then only the engine could be started, he said that this pressure switch has 3 wires, one of them gets the pressure reading to the ECM so that whenever oil pressure goes low, the ECM would be shutting the fuel pump, hence the whole engine right at once. In fact, this is what happened with me. Now I have the 3 wires pressure switch, the 3 wire connector with the brown wire attached to it, yet there is no pressure reading in my gauges instruments panel. This way, this pressure switch is either failing to send a pressure reading to the oil pressure gauge, failing to send a pressure reading to the ECM or failing to do both tasks. Additionally, I will dismantle the coolant temperature sender unit( to the ECM), replacing it to see if the engine stops stalling right after that( I don't have a way of testing it). Today, I drove a whole 110 km to Duhok town and got back, that is about 220 km, the engine stalled more than 20 times giving a tough time, the weird thing is that for 3 times in the least; the RPM pointer dropped down dead but as I was maintaining my foot pressure on the accelerator pedal it simply " resurrected: at once! This phenomena is quite typical in a manual transmission vehicle when the engine stall and you press down the clutch pedal, out the GB lever into some high or medium gear and then take off your foot, the engine gets back to life, how could it be there with my automatic transmission? All the time that the engine was not working smoothly, the speedometer( km/mile counter) would be jumping erratically as I crank the starter motor, as if it has a short circuit malfunction (tachometer and speedometer pointers both jumping high when I turn the starter motor on).