99' Base 5 speed Cranks / No start / No codes / New CPS - Page 2 - 986 Forum - The Community for Porsche Boxster & Cayman Owners

blue62 · 08-30-2019, 06:51 AM

Quote:

Originally Posted by Fiddlebog

blue62 is right.
Another way you can test spark is by pulling a plug out (make sure your fuel pump is disconnected) and grounding it out while cranking. Then you'll have a clear visual cue.

Fiddlebog,
Not a slam on you but that is a bad idea on a multi coil direct to sparkplug system.
use a spark tester made for the purpose. They are around 15 bucks I think. that way you eliminate any chance of mucking up the electrical system

Fiddlebog · 08-30-2019, 06:53 AM

Quote:

Originally Posted by GLImages

I went through something similar. It ended up being a bad idle control valve. The unit on the side of the throttle body. I played with the parts shotgun and replaced just about anything fuel spark related chasing a start, but no crank issue. (Cps, maf, plugs, fuel pump, fuel reg, 02 sens, etc). Finally just happened to hear a slight buzzing from the the throttle body when checking fuel pressure for the 10th time, gave the ICV a couple taps, buzzing stopped, car cranked and ran like normal. Like nothing had been wrong. I put a bosch unit in, no issues since. I had never heard or read of one failing, so I looked over it multiple times. Just throwing that out there.

Sent from my SM-G965U using Tapatalk

Funny you should say that. Same exact thing happened to me. I actually took the whole unit apart and used some QD cleaner on it.
But when I was having the issue, I would still get some sputtering, and sometimes it would start but run really rough. Had a few other weird symptoms before that as well. All cleared up with a good clean though!

blue62 · 08-30-2019, 06:53 AM

Quote:

Originally Posted by Chi-Town

So I have fuel and if I jump the relay I have fuel pressure

At this point I think it's headed to the dealer, I'm out of ideas

Chi
Sounds like you have a no spark problem. Get a spark tester to confirm it, They are around 15 bucks I think.

Fiddlebog · 08-30-2019, 06:55 AM

Quote:

Originally Posted by blue62

Fiddlebog,
Not a slam on you but that is a bad idea on a multi coil direct to sparkplug system.
use a spark tester made for the purpose. They are around 15 bucks I think. that way you eliminate any chance of mucking up the electrical system

Never heard that before. Can you explain why or provide a link to an explanation? Just curious. I've never actually used that trick on a multi coil system, but I guess it's good I haven't.

blue62 · 08-30-2019, 07:06 AM

Quote:

Originally Posted by Fiddlebog

Never heard that before. Can you explain why or provide a link to an explanation? Just curious. I've never actually used that trick on a multi coil system, but I guess it's good I haven't.

Fiddle,
I read about not doing it that way and why not years ago. Don't remember where I read it. or what possible issues could arise. But most likely possibly harmful to the computer system. So I have used a spark tester every since. Cheap insurance.
I am sure you could find reference to it on the web

blue62 · 08-30-2019, 07:58 AM

Chi-town
I just went back and reread this entire thread.

What I would do is stick to the simplest things first method.
So the first thing I would want to know without a doubt is what the overall problem is.
Is it a fuel delivery problem? or a spark delivery problem?. Or both.?

I would test the fuel and ignition systems using starting fluid and a spark tester.
Easy to do, reliable and inexpensive.

If I chase the fuel system when I have an ignition issue I am chasing my tail.
If I chase the ignition system when I have a fuel issue I am chasing my tail.
If I have an issue that affects both systems I don't know what I am chasing

So if I was going to DIY this issue.
I would want to know With out a doubt,is it a fuel issue? an ignition issue ?or both???? (I am beginning to think you have both)
Once I know the answer then I have a solid foundation to my diagnosis and proper direction to procced.

Hope this helps

Chi-Town · 08-30-2019, 06:54 PM

Yeah I need to dedicate some solid diag time to it this weekend.

I tossed a fresh charged battery in it tonight and gave it a good crank, smelled fuel when I held the throttle open.

I'll check for spark in the morning, I've been avoiding it due to the oil leaks on the spark plugs tubes.

Air intake system is clear.

And thanks to everyone for their input and encouragement, it is much appreciated!

Fiddlebog · 08-31-2019, 01:02 AM

The throttle body is definitely acting normally, yes?

particlewave · 08-31-2019, 02:29 AM

Quote:

Originally Posted by blue62

Fiddle,
I read about not doing it that way and why not years ago. Don't remember where I read it. or what possible issues could arise. But most likely possibly harmful to the computer system. So I have used a spark tester every since. Cheap insurance.
I am sure you could find reference to it on the web

Sorry, but this is simply not true.
Just think about it...grounding the plug is doing the exact same thing as happens in the engine block.
Maybe you read it back in the 90’s when people were still afraid of computer controlled cars?

I agree, though: get a tester. It’s much easier.

GLImages · 08-31-2019, 06:11 AM

Quote:

Originally Posted by Fiddlebog

Funny you should say that. Same exact thing happened to me. I actually took the whole unit apart and used some QD cleaner on it.

But when I was having the issue, I would still get some sputtering, and sometimes it would start but run really rough. Had a few other weird symptoms before that as well. All cleared up with a good clean though!

Mine started with sputtering. Then just finally quit starting all together after a couple weeks of chasing my tail. What was throwing me off in my situation was the fuel pressure at the rail with car not running but key on was zero. New pump, regulator, cps, and still zero at the rail. Thankfully, I stumbled on the icv making noise. I swapped in a new one and had the normal 3.8 bar at the rail. I didn't think the ICV was THAT involved in fuel control. Its a simple 2 wire plug, so not sure what the ecu 'sees' from it. So to double check, I swapped the old ICV in and sure enough zero pressure at the rail again.

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blue62 · 08-31-2019, 06:33 AM

Quote:

Originally Posted by particlewave

Sorry, but this is simply not true.
Just think about it...grounding the plug is doing the exact same thing as happens in the engine block.
Maybe you read it back in the 90’s when people were still afraid of computer controlled cars?

I agree, though: get a tester. It’s much easier.

PW
That was my thought as well. And yes I read about it years ago in the 90's I think your comment about fear of computer controlled cars is right on. I still think a 20 dollar spark tester is cheap insurance and as you said less hassle

I believe the fear in the past was in the event of not having a solid ground when laying the plug on the block that somehow all that voltage could possibly jump to a nearby sensor or component thereby doing damage to the computer.

Chi-Town · 08-31-2019, 09:15 AM

Ok, got up early before the heat started and did some basic diag.

Fuel pressure while cranking 34-36 psi

Showed spark on rear cylinder LH side

Pulled the plug, wet with fuel

Tried a squirt of starting fluid no change. (open or closed throttle)

No codes in any Modules

Cranks smooth, no noise

Does anyone have a video of an M96 cranking with a broken timing chain?
I'm thinking there would be a code stored if it broke even if it's only cranking?

I have a spare 2.7 but I was hoping to avoid the engine swap.

blue62 · 08-31-2019, 06:55 PM

Quote:

Originally Posted by Chi-Town

Ok, got up early before the heat started and did some basic diag.

Fuel pressure while cranking 34-36 psi

Showed spark on rear cylinder LH side

Pulled the plug, wet with fuel

Tried a squirt of starting fluid no change. (open or closed throttle)

No codes in any Modules

Cranks smooth, no noise

Does anyone have a video of an M96 cranking with a broken timing chain?
I'm thinking there would be a code stored if it broke even if it's only cranking?

I have a spare 2.7 but I was hoping to avoid the engine swap.

You say it cranks smooth no noise.
you could do a compression check on a few or all cylinders to verify correct valve action. If you have a broken timing chain I would think a piston would have hit a valve by now.
You mentioned oil leaking at the spark plug tubes. How bad? is there any chance that the oil is grounding your plugs out so your not getting spark in the cylinders?

Chi-Town · 08-31-2019, 06:59 PM

Yeah I was thinking it would have smacked a valve and stopped by now also.

No oil on the plugs just flowing out the valve cover side.

I've been thinking about it all day and when I did the fuel pressure it smelled like gas but not as strong as usual.

The car had an aftermarket fuel cap on it and no gas door when I got it.

I'm wondering if the fuel is contaminated? I'll take a sample in the morning before it gets hot and see if it is.

blue62 · 08-31-2019, 07:20 PM

[QUOTE=Chi-Town;602211]Yeah I was thinking it would have smacked a valve and stopped by now also.

No oil on the plugs just flowing out the valve cover side.

I've been thinking about it all day and when I did the fuel pressure it smelled like gas but not as strong as usual.

The car had an aftermarket fuel cap on it and no gas door when I got it.

I'm wondering if the fuel is contaminated? I'll take a sample in the morning before it gets hot and see if it is.[/QUOTE

If your getting spark at the plug you should have got at lease a sputter or cough using the starting fluid.. so my thoughts are
1. plugs are to wet and fouled with possible contaminated fuel that your not get spark at the electroid
2.no compression.
3.hell of a restriction in the intake or exhaust so not drawing in air.

You can check #3 by using a vacuum gauge hooked up at the intake while cranking.
needle should show 3-5 inches? of vacuum at cranking.

you may want to pull all the plugs clean and dry them.

Starting to sound like a carbureted engine with a choke stuck closed LOL

Chi-Town · 08-31-2019, 07:27 PM

I'm thinking there's enough water in it to kill the spark.

It's got vacuum, I can see flow past the MAF

I figure it's lot likely to lose compression on all 6 at the same time?

Fiddlebog · 09-01-2019, 12:01 AM

if you kill the fuel pump and just spray starter fluid in, you should get ignition. If not, it's definitely not a fuel issue.
Is there any way the ignition timing could be off? I worked on an old carb-engine a while back, and the magnet for the hall sensor had gotten out of alignment causing the ignition to be out of phase. Don't know enough about the CPS in these engines to make any conclusions, though.

blue62 · 09-01-2019, 04:09 AM

Chi-town
Did you buy this car as a nonrunner or???????

Chi-Town · 09-01-2019, 08:42 PM

I did buy it not running

Good idea on killing the pump, I'll try that in the morning

blue62 · 09-02-2019, 05:41 AM

Quote:

Originally Posted by Chi-Town

I did buy it not running

Good idea on killing the pump, I'll try that in the morning

Due to the fact that you bought it non running I would do a compression test.
If it comes in ok that eliminates a lot of tail chasing.
If you have compression and your getting good clean fuel and spark into the cylinders you should get it to at least cough or sputter even if spark and valve time are a little off.

If you disable the fuel pump and use the starting fluid as above and have compression and spark you should get some sign of ignition.