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Engine Stopped in middle of acceleration 2nd gear


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Hi all,

Been a long time since I have visited due to things running pretty well until today. I was on my commute home in my 97 Boxster (48K miles) and had been driving for about 30 mins in city traffic. I turned right at a green light and shifted into 2nd and was accelerating. I think I heard a thud / thump and the engine completely died (but the dash lights stayed on like they would if you stalled it). I tried to restart it while I was rolling but no luck, so I was lucky to make it off the road and park it in a parking spot. The oil level and temperature were both fine. Now you hear the starter run, but it just won't turn over. I see all the lights and the radio / top etc works fine, and the starter actually runs (i.e. it makes the cranking noise). I checked all the fuses on the driver's side since my first thought was maybe fuel pump fuse. They were all fine, so I removed the engine cover and made sure the tube from the air filter to the IACV hadn't popped off. It looked fine, and I even tried unplugging the MAF, but still wouldn't turn over.

Now for the interesting part. After my wife picked me up, I got my Elm code reader / digimoto laptop and hooked it up. It was giving me a Bus...Init error when I tried to read codes or look at anything really. I checked it on my wife's car and the code reader is working fine. So not sure where to start with the diagnostics and coming to the gurus for help :) My gut still says fuel pump since it died so suddenly in mid-operation, but I know they don't fail that often and the code reader situation has me wondering. Any thoughts?

Kyrak

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You state twice that motor won't turn over but the stater will. If this is the case either the pinion gear is worn on the starter motor, the sprague clutch is slipping, the solonoid is not engaging the ring gear or the ring gear has an area devoid of teeth from previous damage. These are possible but unlikely.

I think you mean the motor WILL turn over but won't start. If this is the case check fuel pressure at the test port, you can also try cranking the motor for a few seconds and smell the tailpipe for raw fuel. Check for spark too which may be more difficult. Try disconnecting the battery for a couple of minutes and reconnecting it and trying starter.

This is all that comes to mind that you can easily check. Good luck!

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You state twice that motor won't turn over but the stater will. If this is the case either the pinion gear is worn on the starter motor, the sprague clutch is slipping, the solonoid is not engaging the ring gear or the ring gear has an area devoid of teeth from previous damage. These are possible but unlikely.

I think you mean the motor WILL turn over but won't start. If this is the case check fuel pressure at the test port, you can also try cranking the motor for a few seconds and smell the tailpipe for raw fuel. Check for spark too which may be more difficult. Try disconnecting the battery for a couple of minutes and reconnecting it and trying starter.

This is all that comes to mind that you can easily check. Good luck!

Yes, I was worried I was saying it wrong. It makes the normal starting noise, but just doesn't "fire". After doing some more research, I am thinking fuel pump and / or fuel pump relay. I hear some noise when I turn it on, but not really a buzzing. Is there a way to test the relay with a volt-meter/electrical tester? Where is that pressure test port (I read somewhere it is on the passenger side, but not sure where). What kind of tester do I need from Autozone or the like to check the pressure? I did try disconnecting the battery for a few minutes and no luck.

Thanks for your help!

Kyrak

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I just took another look and do think I hear a buzzing when the key is in the on position. I also feel a click in the fuel pump relay when I cut it on as well. Soooo, if the buzzing means the pump is OK, and the click means the relay is ok (which I am not sure is the case), then I am back to square one. I am trying to decide if this is something I should attempt myself or if the dealer will save time and $$ vs swapping out parts that may or may not be bad.

Kyrak

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Perhaps we can find a member with a PST2 or Durametric Software to see what the actual values of some o the sensors are.

I am available this weekend if anyone stumbles onto this thread :) If I don't hear from anyone, I may have it towed to Vertex (indy who someone recommended) tomorrow so they can hit it first thing Monday. Is there any logic to my "relay is clicking so it is working" theory, or could it still be clicking, but still be malfunctioning?

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A long time ago when i used to drive Nortons and Triumphs we used the 'guide'

if the engine dies suddenly, suspect electrics

if it coughs and sputters, then dies, suspect fuel

Jim

You may very well be right. Maybe some wire just broke or something (although not sure which one could make engine stall in mid acceleration). And I imagine that could be easier to fix than a major part anyhow. My difficulties with my ODBII reader (which has worked on this car in the past) would certainly point to an electrical issue.

Kyrak

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Hmm... so your problem was within one of a fill up?

Yes. I guess bad gas could be a possibility, but I would think that would be more of a sputtering or poorly running issue rather than a shut off. But I have seen stranger things.

Kyrak

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Try a bottle of HEET in the gas tank, will mix with any water. Worth a try!

I tried a bottle of HEET with no luck and ended up having it towed to an indy that specializes in Porsches and other exotics. They just took a first glance at it today and it wasn't anything obvious like the fuel pump etc. In the words of the shop manager "I think your computer might have taken a ****" LOL. Which would certainly make sense with everything I have seen so far (sudden stop, bus init error using my ODBII software). The complication is that if it the DME that has gone bad, then it will be hard to get a replacement since the one in there is a Techart version. Anyone have a good source for a new or rebuilt techart DME for a Boxster? I didn't mention because I didn't think it was related, but my box is pretty heavily customized with a bored and stroked 3.0L engine with a 911 camshaft and the TPC supercharger which is why it has the Techart instead of the normal DME. In any case, I will let you know what they find out tomorrow.

Kyrak

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Update: The shop isn't exactly sure what is wrong with it, but thinks it is either the immobilizer or the DME. It is giving an invalid key code message when he connects the PST2 and he was going to get any P codes for me tomorrow. He is recommending replacing the immobilizer first and then if that doesn't work, the DME. I think I am going to cry uncle and take it to the dealer since it doesn't look SC related and is an electrical issue. I need to find out if the dealer will even touch it of course since it has the SC kit etc on it. I am thinking that will be preferable to just buying parts (especially when those parts are the DME and the alarm which aren't exactly cheap.) Let me know if any other answers pop up that could help,

Kyrak

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Unbelievable! My 97 died today also! however mines only went 1/2 block and coast back to my driveway. highly modified with 3.4l upgrade and FVD DME the symptoms are the same start and drive off fine then died and won't restart. just cranks i am having it flatbed to independent tomorrow. Will advise what they find. JES

Edited by jes
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Update: I just got a call from the dealer and it looks like best case scenario! :thumbup: The DME relay had gone bad. So a $35 part instead of a $2000 one. Of course they came up with a laundry list of other things that should / needed to be done. Just FYI, I will include it here:

DME relay, refit boost hoses, reinstall seat and DME $35.18 parts, 3 hours labor, $440.18 total. (this was done to get car running)

Starter is occasionally (maybe 1 in 20 starts) making the squealing noise which they said means it is failing. $578 parts, 3.5 hrs labor, $1051 total.

15K (car is nearing 45K miles) service $750

Brake System Flush $320

Broken Motor Mount $319 parts, 1.5 hr labor, $521 total

Leaking Oil Breather Hose $35 parts, 1.5 hr labor, $237 total

Reroute Idle & Throttle position sensor wires (relocated due to the supercharger but rubbing against the transmission in their current spot) 2 hrs labor $270.

I had them do the DME relay, the breather hose, and the rerouting of the throttle sensor to keep the costs somewhat under control and will plan for the motor mount and the starter in the future.

So really the total to get it running again was $500 for the first indy (labor only troubleshooting fuel pump, computer etc etc) and $440 for the dealer to actually find and fix what was wrong. This is one of those situations where if I had taken it directly to the dealer instead of the indy, it would have been maybe $300 or so. My advice for anyone with strange electrical issues is take it to the dealer since they got to the root of the problem quickly where the indy was ready to start buying parts (contrary to how it normally is, eh?)

Thanks guys for your help in troubleshooting this, and if you read the advice above, it certainly applies to the end result of the relay.

Kyrak

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Kyrak, DME relay? do you have part #. My shop couldn't take my car until Monday but if this relay is user replaceable i will try it Thanks in advance. JES

From what I can tell, it looks like it is part 141-951-253-B-M5206. You can see it in a diagram at http://www.pelicanparts.com/PartsLookup/HT...2-01-Frame3.htm . I am not sure where this relay box is other than "rear end" and am not sure how hard it is to get to. Anyone else know how to get to this set of relays?

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