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Engine non-start, need help!


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I am stuck in my install of a used 3.2 liter m96 motor in my 2001 Boxster S.

Donor was a 2000 Boxster S. The motor is back in the car and I attempted to start it before I put the exhaust, muffler and assorted braces back in place. My logic is that if I had problems I could save those steps in pulling the motor back out. I have a couple of coolant leaks to address, but the big issue is that the starter does not engage. Key in the ignition, power is on, accessories are on, turn the key and no change at all.

Is there anything that must be done from an electronic standpoint to reset ECU when the motor has been out or switched?

I have checked the battery and it is good. Even tried to use a jump box to help and still the exact same response. Key turns but the accessories and lights continue and no starter.

So here is what I have done.

I reconnected the two fuel lines on the firewall driver's side.

I reconnected the fuel rail return line at the rear of the engine bay passenger side.

I reconnected the power steering lines.

I have reconnected all coolant hoses.

I reconnected the harness to the ECU.

I secured the harness ground in the trunk.

I plugged in the AFM.

I reconnected the GP 14 to the chassis beside the secondary air pump.

I reconnected the b+ terminal wires.

Plugged in reveres sensor switch.

Reinstalled slave cylinder on the transmission

Reconnected secondary air pump.

Plugged in engine bay fan and secondary air pump to engine harness.

Reinstalled AC compressor and reattached fun clutch wire.

Reconnected brake vacuum booster.

What am I missing? Is there some devious reason why the mid pipes and muffler would need to be installed?

Thanks

Edited by mr2by4
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I am stuck in my install of a used 3.2 liter m96 motor in my 2001 Boxster S.

Donor was a 2000 Boxster S. The motor is back in the car and I attempted to start it before I put the exhaust, muffler and assorted braces back in place. My logic is that if I had problems I could save those steps in pulling the motor back out. I have a couple of coolant leaks to address, but the big issue is that the starter does not engage. Key in the ignition, power is on, accessories are on, turn the key and no change at all.

Is there anything that must be done from an electronic standpoint to reset ECU when the motor has been out or switched?

I have checked the battery and it is good. Even tried to use a jump box to help and still the exact same response. Key turns but the accessories and lights continue and no starter.

So here is what I have done.

I reconnected the two fuel lines on the firewall driver's side.

I reconnected the fuel rail return line at the rear of the engine bay passenger side.

I reconnected the power steering lines.

I have reconnected all coolant hoses.

I reconnected the harness to the ECU.

I secured the harness ground in the trunk.

I plugged in the AFM.

I reconnected the GP 14 to the chassis beside the secondary air pump.

I reconnected the b+ terminal to the ground strap.

Plugged in reveres sensor switch.

Reinstalled slave cylinder on the transmission

Reconnected secondary air pump.

Plugged in engine bay fan and secondary air pump to engine harness.

Reinstalled AC compressor and reattached fun clutch wire.

Reconnected brake vacuum booster.

What am I missing? Is there some devious reason why the mid pipes and muffler woudl need to be installed?

Thanks

Have you checked the clutch interlock switch? The symptoms sound similar (i.e., accessories on, etc.).

Also, it wouldn't hurt to connect a jumper cable from the negative terminal of the battery to the engine, just to make sure you have a good ground there.

Regards, Maurice.

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Have you checked the clutch interlock switch? The symptoms sound similar (i.e., accessories on, etc.).

Also, it wouldn't hurt to connect a jumper cable from the negative terminal of the battery to the engine, just to make sure you have a good ground there.

Regards, Maurice.

I suspected a safety switch like clutch interlock, but it was not affected by the repairs. I suppose it could have just been bad luck.

Thanks for the suggestion about grounding the motor to the battery.

I will try those both.

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Well I tried the negative cable to check grounds.

No luck

I tried to bump the starter at the terminals to see if it would turn over.

It cranks but no fire. Not sure if I am getting fuel or not. Does not smell like it. I am guessing that whatever is trying to keep me from using the starter is blocking the FP as well.

HELP!

Is it possible that the engine block(or other security) feature of the ECU has kicked in since it was disconnected?

Edited by mr2by4
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Well I tried the negative cable to check grounds.

No luck

I tried to bump the starter at the terminals to see if it would turn over.

It cranks but no fire. Not sure if I am getting fuel or not. Does not smell like it. I am guessing that whatever is trying to keep me from using the starter is blocking the FP as well.

HELP!

Is it possible that the engine block(or other security) feature of the ECU has kicked in since it was disconnected?

Well I am wondering if you bolted the transmission mounts to body with the correct ft/lbs, some times a slight difference in the way the transmission connect to engine might stop the engine from starting. I say tighten the transmission mount, engine mount to body according to factory specs see if that helps. Good luck :)

Ali

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Well I tried the negative cable to check grounds.

No luck

I tried to bump the starter at the terminals to see if it would turn over.

It cranks but no fire. Not sure if I am getting fuel or not. Does not smell like it. I am guessing that whatever is trying to keep me from using the starter is blocking the FP as well.

HELP!

Is it possible that the engine block(or other security) feature of the ECU has kicked in since it was disconnected?

It may be worthwhile to verify that you are getting fuel (for your 2001 S/2000 S motor).

You can bypass the fuel pump relay and thus power the fuel pump directly. Pull off the fuel pump relay that is in the relay carrier above the fuses (driver's side footwell/kick panel). It's the fuse that is immediately to the left of the double relay for the convertible top, so the fuel pump relay is third from the right, and third row up from the bottom, with no relays in the bottom row. Then, you can make up a length of wire and, to be safe, put in a 15amp fuse inline before you connect the two terminals on the relay panel. The terminals on the relay are labeled 30 and 87, with the corresponding tabs on the relay panel that you have to jump being numbered 3 and 5.

Before you jump the wires, if you have already replaced the rearmost plastic underside panel, remove it. Then disconnect (i.e., separate) the fuel return line at the driver's side front of the engine and get ready to catch the fuel in a suitable container.

As soon as you jump the wires, the fuel pump will start to run and you should get fuel coming out of where you disconnected the fuel return line. If you want to go further and check the volume, the specification is about 9/10ths of a quart with 30 seconds of fuel pump operation.

Of course, BE EXTREMELY CAREFUL WITH SPARKS, HOT LIGHT BULBS, ETC. when you are doing ANY OF THIS WORK. :angry:

If you have fuel, you will have eliminated that as a possible cause for non-start and it should not take too long to run this test, and then you will know that it is only an electrical (or electronic) cause for the fuel pump not getting a signal to run.

Regards, Maurice.

Edited by 1schoir
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Well I am wondering if you bolted the transmission mounts to body with the correct ft/lbs, some times a slight difference in the way the transmission connect to engine might stop the engine from starting. I say tighten the transmission mount, engine mount to body according to factory specs see if that helps. Good luck :)

Ali

Are you saying the bolts that mount the transmission to its y-braces or the bolts through the transmission mounts should have torque verified?

This sounds insane that it would result in total engine (ECU)immobilization, but I am willing to give it a try.

Thanks

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It may be worthwhile to verify that you are getting fuel (for your 2001 S/2000 S motor).

<SNIP>

Regards, Maurice.

I am not getting fuel.

I am not getting spark. I am not energizing the starter.

It appears that everytihng is hot (I can jumper the starter) but no fire. So the fuel pump relay is not my primary concern.

I will use this process to verify fuel pump function if I can get the car to respond to the ignition and it still will not fire.

Thanks!

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Well I am wondering if you bolted the transmission mounts to body with the correct ft/lbs, some times a slight difference in the way the transmission connect to engine might stop the engine from starting. I say tighten the transmission mount, engine mount to body according to factory specs see if that helps. Good luck :)

Ali

Are you saying the bolts that mount the transmission to its y-braces or the bolts through the transmission mounts should have torque verified?

This sounds insane that it would result in total engine (ECU)immobilization, but I am willing to give it a try.

Thanks

I mean transmission support to transmission, and transmission to body, also engine to body. I think its about 48ft/lbs. for example let say the transmission to body is at 38ft/lbs while engine to body at 48ft/lbs, that means transmission sets lower than engine. You want to make sure they both set at the same level evenly. if you turn the ignition on, and you get power, and you hear the starter clicks but no engine start "starter does not engage", then that might be the case here.

Ali

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I'm not sure for US cars, check this furst

you need the DME from the 3.2 donor car, ATT. DME for TIP. is not the same as for the MAN. gearbox ( if it is the case )

You need the alarm control box from the 3.2 donor car

You need the remote control from the 3.2 donor car

Wiring can be different

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Are you using your old DME? If not then the new DME must be matched to the immobilizer code in your car.

If this is not the case and you are sure the wiring is correct make sure and check fuses C1-C4, in particular C1.

The fact you have not added the braces and exhaust will not prevent the car from running.

The process of 'jumpering' components is not one I would recommend. Electronics are expensive and easily fried. If these components worked before your engine swap, it is obviously most likely it is something you have done during the swap process and not a new failure of the fuel pump etc.

Todd

Edited by tholyoak
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I mean transmission support to transmission, and transmission to body, also engine to body. I think its about 48ft/lbs. for example let say the transmission to body is at 38ft/lbs while engine to body at 48ft/lbs, that means transmission sets lower than engine. You want to make sure they both set at the same level evenly. if you turn the ignition on, and you get power, and you hear the starter clicks but no engine start "starter does not engage", then that might be the case here.

Ali

No clicks, just nothing.

I don't see that the angle of the engine n the body would affect the ECU. The car will start on a hill. It will aslo run with spacers of unequal size front and rear (such as in a 3.4 swap).

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Are you using your old DME? If not then the new DME must be matched to the immobilizer code in your car.

If this is not the case and you are sure the wiring is correct make sure and check fuses C1-C4, in particular C1.

The fact you have not added the braces and exhaust will not prevent the car from running.

The process of 'jumpering' components is not one I would recommend. Electronics are expensive and easily fried. If these components worked before your engine swap, it is obviously most likely it is something you have done during the swap process and not a new failure of the fuel pump etc.

Todd

Same old DME. If I disconnected it. will it need to be reset to the immobilizer?

I will check those fuses.

Other than checking that I had power at the starter, I have been saving those things for a last resort. I don't want to know what Porsche charges for a fuel pump!

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Well disconnecting it should not do anything to the DME. Although I bought a used 996 dme once and when I received it and hooked it up to the PST2, it was blank. So I had to reprogram it from scratch. So I guess anything is possible. I would check the fuses first.

Todd

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DME!

Yes, thats very helpful. That is what I suspected, but what about it?

The car is a MY2001 Boxster S, the motor and engine harness are from a MY2000 Boxster S.

They should be 100% compatable.

I am using the dme and immobilizer from my car.

Does the clutch safety just disable the starter or the entire DME(fuel, ignition etc)?

If it was the clutch switch should jumping the starter have gotten me running?

I talked with two shops today and they are convinced that it is not the immobilizer. Since the door locks and remote are working.

They insist that there is no reset of the immobilizer. Should I just take in the DME(the whole car) and have them look at it?

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The clutch switch provides a ground signal to the DME, without it the starter relay will not be energized. If after checking the basics it all checks out, you need to hook it up to a pst and find out what the problem is.

Todd

Edited by tholyoak
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The clutch switch provides a ground signal to the DME, without it the starter relay will not be energized. If after checking the basics it all checks out, you need to hook it up to a pst and find out what the problem is.

Todd

So would this signal completely kill the dme prior to start-up? (ignition, injection and starter)

I aks b/c with the ignition on I cranked the motor with remote starter switch on the starter terminals and it would not fire (no fuel, no spark)

I am going to check this switch and those 2 fuses and if that does not fix it, I am going to take it by RUF to have them hook the DME up to the computer.

Thanks!

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No, just the starter. The DME relay and injection relays are turned on before the starter lock relay. The output from the DME relay provides the low amp + input to the starter lock relay, the DME via the pedal switch controls the ground which actuates the closure of the high amp side of the relay sending current to the starter.

Check the fuses, it will take 5 seconds.

Todd

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Fuses were fine. So was clutch swicth.

Reaching a total stand still I decided to go back over everything I could and found that the smallest of the looms attached on the bottom of the ecu was not entirely plugged in.

Pushed it all the way in and checked all of the other plugs one more time and it cranked. Took a minute to build fuel pressure and then fired.

Runs just fine.

Now to put the mufflers etc back on!

Thanks for all of the suggestions.

Sorry it was such a stupid mistake, but happy that it is solved!

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Fuses were fine. So was clutch swicth.

Reaching a total stand still I decided to go back over everything I could and found that the smallest of the looms attached on the bottom of the ecu was not entirely plugged in.

Pushed it all the way in and checked all of the other plugs one more time and it cranked. Took a minute to build fuel pressure and then fired.

Runs just fine.

Now to put the mufflers etc back on!

Thanks for all of the suggestions.

Sorry it was such a stupid mistake, but happy that it is solved!

Good work!

It seems that almost every time that one pulls and re-installs an engine, this type of thing happens. It's good to walk away from it sometimes and then go at it again. The sound of the engine firing must have been sweet indeed.

Congratulations!

Regards, Maurice.

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I believe it was mentioned early on to check your wiring connections before chasing something more complicated hmmm ;)

Do you know how many times I looked at those and thought, "well all of those are connected"

The small plug at the bottom lacks the cam lock so it was not obvious that it was disconnected until I started trying to pull things out and put them back in. I suppose the lesson here is that sometimes you should not trust your eyes. You need to put your hands on it to be sure.

Thanks again!

Just as an afterthought,

Boy is a Boxtser loud with only the headers on and both of the engine panels out.

Suprisingly loud , in addition to combustion sounds, is the air pump.

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