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Nov. 25, 2008 8:58 a.m. SoloSonett Reader

Just learning to tune in the 21st century! LOL Electrical gremlins are a B^*(&%

I had a 1968 Ford Galixie 500 GT with a 302.. Huge fast back that was geared to run 120 all day long after 2 mins of acceleration.

Getting long in the tooth, 1974 75 I was crusing to work 20 miles and every day! I would hit a very slight incline on the freeway and it would cut off , dead. Same spot, Car re-started and ran great after.

Took it back to my old gas station and did the same "drive " and loads on an old ossciliscope. And found a dead short from the coil to .... a hose clamp on a heater hose on the manifold!

Moved the coil and gremlin excised!

Also learned the hard way... double check the ground!
Nov. 25, 2008 9:49 a.m. Jensenman UltimaDork

pigeon wrote:

GVX19 wrote:

Jensenman wrote:

If I am reading this right, you have NO fuel trim, short or long. 99.6% engine load at 2000RPM? Hmmm.

Yes but if you look more closely. You will see that is not the biggest problem it has. The fuel trim is just telling you that, the ecm is happy runing at 14.7 afr.

Was that thing boosted? MAP is showing something like 4PSI over atmospheric, right?

Yeah, there is SOMETHING weird happening there.

Speaking of weird driveability problems: I had a customer with a KIA Sportage who would come in with a MIL at least once a week. The code was always a stored (not current or active) P0101, MAF insufficient flow. We had put a MAF on it to no avail, it was getting pretty hairy because the customer was PISSED.

So on the last visit, my tech and I are looking the thing over and he glances up, notices there is a 'button' retainer missing from the hood insulation pad and there's a crease. A little eyeball measuring shows that the leading edge of this bent piece is in the area of the air filter snorkel. The light goes on: at highway speeds air rushing in would bow the unsecured edge down and it would block the air intake, cut the airflow and set the P0101. One button retainer later, it never did it again.
Nov. 25, 2008 8:18 p.m. GVX19 New Reader

Jensenman wrote:

pigeon wrote:

GVX19 wrote:

Jensenman wrote:

If I am reading this right, you have NO fuel trim, short or long. 99.6% engine load at 2000RPM? Hmmm.

Yes but if you look more closely. You will see that is not the biggest problem it has. The fuel trim is just telling you that, the ecm is happy runing at 14.7 afr.

Was that thing boosted? MAP is showing something like 4PSI over atmospheric, right?

Yeah, there is SOMETHING weird happening there.

Speaking of weird driveability problems: I had a customer with a KIA Sportage who would come in with a MIL at least once a week. The code was always a stored (not current or active) P0101, MAF insufficient flow. We had put a MAF on it to no avail, it was getting pretty hairy because the customer was PISSED.

So on the last visit, my tech and I are looking the thing over and he glances up, notices there is a 'button' retainer missing from the hood insulation pad and there's a crease. A little eyeball measuring shows that the leading edge of this bent piece is in the area of the air filter snorkel. The light goes on: at highway speeds air rushing in would bow the unsecured edge down and it would block the air intake, cut the airflow and set the P0101. One button retainer later, it never did it again.

That is crazy! can you get me photo so I can see just what your talking about. I dont wont to spend a week learning that one the hard way.
Nov. 25, 2008 8:33 p.m. GVX19 New Reader

pigeon wrote:

GVX19 wrote:

Jensenman wrote:

If I am reading this right, you have NO fuel trim, short or long. 99.6% engine load at 2000RPM? Hmmm.

Yes but if you look more closely. You will see that is not the biggest problem it has. The fuel trim is just telling you that, the ecm is happy runing at 14.7 afr.

Was that thing boosted? MAP is showing something like 4PSI over atmospheric, right?

No it was not. It looks like this ECM Is programed for a boosted sys. It not only adds fuel under boost it retards the timing. That is all good if you have a turbo but if you dont. You loose lots of power. ~ 98% . The MAP was bad. I wish that it did not take me weeks to find that. SnapOn needs to do better with the MODIS. It only lets you see a little at a time. What you see is what you get is not what I wont for $5k.
Nov. 25, 2008 9:17 p.m. Jensenman UltimaDork

So that's a full screenshot? Man, no wonder it took a while. It would have been good to see the MAP voltage.

This pic doesn't show the very front of the hood pad but you can see the engine air 'snorkel' in the middle. The pad is the dark gray stuff under the hood and it's molded to fit with those 'Christmas tree' push retainers all around.

Funny footnote: my tech was er, girthy. OK, he's huge. He leaned over the radiator core support of another similar Sportage that was running, his belly blocked the air intake and set, you guessed it, a PO101. <
Nov. 25, 2008 9:27 p.m. pigeon Reader

GVX19 wrote:

pigeon wrote:

GVX19 wrote:

Jensenman wrote:

If I am reading this right, you have NO fuel trim, short or long. 99.6% engine load at 2000RPM? Hmmm.

Yes but if you look more closely. You will see that is not the biggest problem it has. The fuel trim is just telling you that, the ecm is happy runing at 14.7 afr.

Was that thing boosted? MAP is showing something like 4PSI over atmospheric, right?

No it was not. It looks like this ECM Is programed for a boosted sys. It not only adds fuel under boost it retards the timing. That is all good if you have a turbo but if you dont. You loose lots of power. ~ 98% . The MAP was bad. I wish that it did not take me weeks to find that. SnapOn needs to do better with the MODIS. It only lets you see a little at a time. What you see is what you get is not what I wont for $5k.

Yeah, I was getting at a bad MAP sensor the smartass way. Not bad if I say so myself, considering I'd never seen that type of screen before, and I'm only a shadetree mechanic at best! Actually shadetree is probably the best description for my skills, as there aren't any trees at all on my property! I guess you should post up all your hard to solve problems here, you'll have the answer in a day or so...
Nov. 25, 2008 9:33 p.m. GVX19 New Reader

That is funny. Im trying not to get that big. Im loosing.

Yes that is the screenshot. If you need more info ask god to help you make the car to act up agan. so you can scrol down to the other PIDs. It only took over 20 a temps to get that one. it was not fun. but so rewording when i got it.
Nov. 25, 2008 9:42 p.m. GVX19 New Reader

Pigeon, I have tried that but I usually have an answer be for any one.

http://grassrootsmotorsports.com/forum/grm/help-i-need-a-photo-of-a-crankshaft-pul...