Technical Gauges acting crazy, cranking but won't start

[Hurka]

Hi!

I have a 2003 1242ccm petrol 44kW.
Today while driving the rpm suddenly fell back from 2300rpm to 1800rpm after this was nothing wrong with it. When I stopped for the second time the engine cut off. I tried to restart it but the gauges went crazy. The speedometer rised up to 20km/h, the enigine’s temperature indicator went up and down, and itt took very long for the lights to siwtch off. The car is cranking by the way. The key icon randomly keeps switching on and off with each ignition. I tried two different keys. When it started after many tries the engine went off while driving around 40km/h. After I started it again it had the same symptoms. I pulled up on the side of the road, it shutted down on idle. The fault code from the ECU is U1600 and U1601.
The car did this several days before expect the rpm issue. Back then I soldered the end of the cable which is go from the battery to the engine fuse box. (The other cables are soldered too expect this one, that's why I did it.) The problem went away, but today this happend.

Does anyone have any idea?

Thank you!

 

[AndyRKett]

I think you need to rule out a problem with the battery and alternator before worrying about other things.

If the alternator has died it’s perfectly possible that in combination with a good battery the car would die as the battery flattens but a good battery can recover to the point of being able to start the car again after a while

 

[varesecrazy]

Hi!

I have a 2003 1242ccm petrol 44kW.
Today while driving the rpm suddenly fell back from 2300rpm to 1800rpm after this was nothing wrong with it. When I stopped for the second time the engine cut off. I tried to restart it but the gauges went crazy. The speedometer rised up to 20km/h, the enigine’s temperature indicator went up and down, and itt took very long for the lights to siwtch off. The car is cranking by the way. The key icon randomly keeps switching on and off with each ignition. I tried two different keys.

Does anyone have any idea?

Thank you!

Is the alternator putting in a sensible charge.. @14v ?

 

[Hurka]

We tried a jump start but it did the same thing and didn't start. I heard that one relay was kept clicking. I can't post pictures and links yet that's why I write it. Please paste this: "a/6oLZO2d" next to the imgur's link. In this picture is the R3 relay. When I swapped it with another one that was clicking too. Without it, the instruments worked normally. On ignition just this relay's coil voltage dropped below 12V. Today we just had time for this.

 

[judderbar]

1. There is a feature called 'follow me home' that leaves the headlights on with the ignition off. So that could be a normal problem caused by another error.


2. The coil voltage for the engine compartment relays comes from the ECU. A little under 12V could be normal. Battery voltage will be about 12.4 volts

I suspect a simple wiring fault.


When the ignition is turned on you should hear the pump work under the back seat for about 5 seconds. This should happen every time the ignition is turned on. The pump is not pressure controlled. Continually random clicking relays does not sound normal.

Check the earth wire for the ECU is good.

There are about 10 earth wires connected to a block just forward of the battery- The block is bolted to the car and the earth wire that goes to the gearbox.

 

[varesecrazy]

We tried a jump start but it did the same thing and didn't start. I heard that one relay was kept clicking. I can't post pictures and links yet that's why I write it. Please paste this: "a/6oLZO2d" next to the imgur's link. In this picture is the R3 relay. When I swapped it with another one that was clicking too. Without it, the instruments worked normally. On ignition just this relay's coil voltage dropped below 12V. Today we just had time for this.

Personally..

I would put a different battery in there.. for a test

If your battery is shorted inside it will make jumpstarting really difficult

Will take 5 minutes to connect up a different battery.. you dont need to bolt it down

 

[Hurka]

1.
When the ignition is turned on you should hear the pump work under the back seat for about 5 seconds. This should happen every time the ignition is turned on. The pump is not pressure controlled. Continually random clicking relays does not sound normal.

Thank you for the tip. We heard the pump kept clicking along with relay. As we removed the cable from the pump the relay and gauges worked normally.
I think I need a new pump.
Thank you and thanks the other answers too!

 

[judderbar]

Thank you for the tip. We heard the pump kept clicking along with relay. As we removed the cable from the pump the relay and gauges worked normally.
I think I need a new pump.
Thank you and thanks the other answers too!

But how can the pump cause such a large current flow from the fusebox that it causes the body computer/other devices to malfunction? The pump relay should be fused in the engine fuse box. The battery should easily be able to deliver voltage to the rest of the car if the pump is over loaded.

The pump current could be a distraction from another wiring problem.

The pump relay large contacts should be permanently connected to the battery even with the ignition off. So even with the ignition off, if you bridge those large contacts the pump should run. You can then measure voltage at the large contacts when the pump does not run and see what happens. The pump earth goes via a switch just above/inside the carpet on the right hand side. Near the right knee of the front seat passenger. Other devices are connected to that Earth. So an earth wire comes from near the battery to the right side of the passenger area. Then you have other earths for other devices at that point, all bolted to the switch. . Then the crash/inertia switch feeds the pump.

As these cars get older all of these earths begin to get resistances at the connections.

In summary. If the pump takes a large current the pump fuse should blow. So it sounds like the normal pump current is distracting you from a wiring fault elsewhere.

 

[Hurka]

But how can the pump cause such a large current flow from the fusebox that it causes the body computer/other devices to malfunction? The pump relay should be fused in the engine fuse box. The battery should easily be able to deliver voltage to the rest of the car if the pump is over loaded.

The pump current could be a distraction from another wiring problem.

The pump relay large contacts should be permanently connected to the battery even with the ignition off. So even with the ignition off, if you bridge those large contacts the pump should run. You can then measure voltage at the large contacts when the pump does not run and see what happens. The pump earth goes via a switch just above/inside the carpet on the right hand side. Near the right knee of the front seat passenger. Other devices are connected to that Earth. So an earth wire comes from near the battery to the right side of the passenger area. Then you have other earths for other devices at that point, all bolted to the switch. . Then the crash/inertia switch feeds the pump.

As these cars get older all of these earths begin to get resistances at the connections.

In summary. If the pump takes a large current the pump fuse should blow. So it sounds like the normal pump current is distracting you from a wiring fault elsewhere.

We connected the pump directly through the engine fuse box. And you were right, it is working perfectly. We measured the cables,the switch below the glowbox. We noticed that whenever we disconnected and reconnected the battery the problem gone for temporary. Found out the battery terminal is made from aluminium and it has a fake cooper coating. We changed it with solid cooper and also cutted off the soldered cable ends. After this everything worked fine expect that the car won't start. The spark is missing. I hope it's the imo. Today we put in a fully charged battery and try it out with different key because this one is a copy.

 

[Hurka]

The imo won't read the keys and the coil voltage is 1.6V.

 

[Hurka]

The imo won't read the keys and the coil voltage is 1.6V.

After the battery was disconnected it reads the keys but the battery light is on and the voltage is the same.

 

[judderbar]

The imo won't read the keys and the coil voltage is 1.6V.

One side of the coils should be battery voltage and the other side is going to be grounded electronically by the ECU when the engine turns over if all is correct.

If the key code light is out the ECU should put battery voltage on one of the red relays to put battery voltage on the coil.

You have many problems most likely coming from a single fault.

Other posters have suggested the battery is faulty. Could be.

Other things being equal if you have 12.4 volts at the battery even with a bad battery and the key code light is out you should have i believe battery voltage at one wire of the coil. I dont think the crash switch changes that and it seems your crash switch is good anyway - very unlikely to be faulty.

Make sure the ECU has a good earth. Apparently you have two faults for the pump and the coils related to the ECU not energising the relay coils. Since the car has been running now and then it is not likely the ECU has actually completelty failed.

All those weird glitches with the instruments could be because of a bad earth.

 

[Hurka]

One side of the coils should be battery voltage and the other side is going to be grounded electronically by the ECU when the engine turns over if all is correct.

If the key code light is out the ECU should put battery voltage on one of the red relays to put battery voltage on the coil.

You have many problems most likely coming from a single fault.

Other posters have suggested the battery is faulty. Could be.

Other things being equal if you have 12.4 volts at the battery even with a bad battery and the key code light is out you should have i believe battery voltage at one wire of the coil. I dont think the crash switch changes that and it seems your crash switch is good anyway - very unlikely to be faulty.

Make sure the ECU has a good earth. Apparently you have two faults for the pump and the coils related to the ECU not energising the relay coils. Since the car has been running now and then it is not likely the ECU has actually completelty failed.

All those weird glitches with the instruments could be because of a bad earth.

We removed the ecu. On the pins and in the connectors are some kind of jelly. And oxid on the casing.

PS.: The last mechanic who worked on the car was repaired the cylinder head. It is possible that this jelly got into it then?

 

[judderbar]

We removed the ecu. On the pins and in the connectors are some kind of jelly. And oxid on the casing.

PS.: The last mechanic who worked on the car was repaired the cylinder head. It is possible that this jelly got into it then?

Those connections are sealed against any liquids getting in them. Must have been put there as some kind of miracle electrical contact enhancer or something or other. Not standard.

 

[Hurka]

We cleaned the ecu and its connectors. The key light was constantly on and could not connect to the OBD (cheap bluetooth type). After we removed the reader then there was no problem with this. The voltage remained the same. It is possible that the ecu see that the ignition coil's connector was removed? Because after we put it back there was a spark from the spark plug cable. And it was started with starting fluid. The check engine was on and we went around the block. When the rpm reached 3000 the engine stopped. Is this some kind of service mod that stops the car at high rpm because of the error codes? After we cleared the fault codes from ecu with normal OBD reader everything went fine.

 

[judderbar]

We cleaned the ecu and its connectors. The key light was constantly on and could not connect to the OBD (cheap bluetooth type). After we removed the reader then there was no problem with this. The voltage remained the same. It is possible that the ecu see that the ignition coil's connector was removed? Because after we put it back there was a spark from the spark plug cable. And it was started with starting fluid. The check engine was on and we went around the block. When the rpm reached 3000 the engine stopped. Is this some kind of service mod that stops the car at high rpm because of the error codes? After we cleared the fault codes from ecu with normal OBD reader everything went fine.

I think the car should run fine with uncleared error codes.


Can you clarify what is happening with that voltage? From the coil?

 

[Hurka]

I think the car should run fine with uncleared error codes.


Can you clarify what is happening with that voltage? From the coil?

We tried to mesaure the voltage which come from the engine control relay to the ignition coils. Unplugged the connector from the coil connected to the multimeter and at ignition it showed 8.2V and after few sec it dropped down to 1.2V. After put the connector back we removed one cable from one of the spark plug and it sparkled. That's why we think that the ecu can sense that there is no cable on the coil. But maybe that is a nonsense.

 

[judderbar]

We tried to mesaure the voltage which come from the engine control relay to the ignition coils. Unplugged the connector from the coil connected to the multimeter and at ignition it showed 8.2V and after few sec it dropped down to 1.2V.

That voltage is just totally wrong! So it should be simple to trouble shoot the problem and find the fault


The power for the coil is coming directly from the battery via the relay. Since you have volts there with the coil not connected, those volts should only be coming directly from the battery via the fuse box.

Even with the ignition off one of the large contacts of the red relay needed for the coil should be able to produce a very healthy amount of current flow and still have close to battery voltage.

Battery voltage and one of the large contacts of the red relay and the coil voltage should be very similar and the possible current flow should be sufficient to light a head light. The coil needs 20 amps of current to operate.

 

[Hurka]

That voltage is just totally wrong! So it should be simple to trouble shoot the problem and find the fault


The power for the coil is coming directly from the battery via the relay. Since you have volts there with the coil not connected, those volts should only be coming directly from the battery via the fuse box.

Even with the ignition off one of the large contacts of the red relay needed for the coil should be able to produce a very healthy amount of current flow and still have close to battery voltage.

Battery voltage and one of the large contacts of the red relay and the coil voltage should be very similar and the possible current flow should be sufficient to light a head light. The coil needs 20 amps of current to operate.

I measured the voltages while everything were on it's own place. On the coil there was the battery's voltage. After started the engine then the coil and the output had the generator's voltage.


By the way the deleted error codes were:
P0120 (probably because we pushed the throttle when we tried to start?)
U1600 (the key light problem disappeared after removed the bad obd)
U1601
P0230 (the connector was removed for testing)