Throttle stuttering on acceleration

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Guy

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I think you’ve got other issues with your truck.

Something is amiss. No pun intended.




I figured I'd take a shot with the plugs so I swapped them out last night. Went with the 542's but left them at stock gap. They came at the same gap as the stock plugs I pulled out, close to .30

Stock plugs that came out looked fine.

I didn't get to drive the truck much yet but it doesn't seem to have changed the issue I'm having. I'll have chance to drive it more later today. If the problem didn't get fixed I'll pull the plugs and drop the gap to .25

Also waiting to hear back from Hotline on their next move

Sledgehammer I've run several tanks of 93 through my truck and my symptoms never changed.
 

03'Darin

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I think you’ve got other issues with your truck.

Something is amiss. No pun intended.

Sure looks that way.

What's crazy is that the truck just feels exactly like an engine miss. Like the early stages of when a COP went out on a 5.4

I was sure a CEL would come on eventually and point us right to the problem. That's one reason I didn't rush in to doing anything.

I was so sure it was plugs that I was just going to do the plug change first and not even have our shop look at it. But when the CEL never came on I decided to do some diagnostic before I just threw plugs at it. After we did the PCM & TCM update it seemed to help it a little. However that only lasted for a short time and it was back to normal. We're pretty sure that had something to do with the adaptive learning period of the tranny.
 

Ckhris

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My plugs 15k miles
attachment.php
 

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03'Darin

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Drove the truck quite a bit last night. Plugs made no improvement at all and may have made it slightly worse.

Hotline responded again. When they originally told us to monitor the torque converter pids looking for slippage they say anything over 100 rpms of slippage wasn't acceptable. That was apparently a typo because they've now said 10 rpms of slippage. So we need to go check that again. If over 10 rpms of slippage they want us to replace the torque converter. If 10 or less they want us to monitor the down stream cat 02 sensors. Tech doesn't think the 02 monitoring will help because those 02's respond to slow.

Hopefully we'll get time today to do more data logging

---------- Post added at 10:40 AM ---------- Previous post was at 10:37 AM ----------

My plugs 15k miles
attachment.php

Look similar to my plugs with 22k miles. My plugs are a little more consistent gray on the porcelain area though.
 

Guy

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Mine way more chocolate at 15k.



Drove the truck quite a bit last night. Plugs made no improvement at all and may have made it slightly worse.

Hotline responded again. When they originally told us to monitor the torque converter pids looking for slippage they say anything over 100 rpms of slippage wasn't acceptable. That was apparently a typo because they've now said 10 rpms of slippage. So we need to go check that again. If over 10 rpms of slippage they want us to replace the torque converter. If 10 or less they want us to monitor the down stream cat 02 sensors. Tech doesn't think the 02 monitoring will help because those 02's respond to slow.

Hopefully we'll get time today to do more data logging

---------- Post added at 10:40 AM ---------- Previous post was at 10:37 AM ----------



Look similar to my plugs with 22k miles. My plugs are a little more consistent gray on the porcelain area though.
 

03'Darin

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We data logged the truck again yesterday.

Watched torque converter pids for slippage and MAP and Boost sensors.

Ford initially said 100 RPMS of variance with tq converter slippage was ok but their last communication said 10 RPM. Our tech said all of the Ford training schools he's been to about transmissions have always said 100 RPM of slippage or less shouldn't be detectable by the average driver. So he thinks the last communication of 10 RPMS variance was wrong. We're waiting on clarification. It had as much as 60 RPMS of slippage but no where near 100.

Ford suspected a possible bad MAP sensor but those readings are all within specs.
 

Ckhris

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Thanks for keeping us informed
Good stuff

My plugs didnt fix my surging either
I did find a smooth road and data logged it. Im gonna send it to MPT after I data log stock too.

I was thinking of looking at all the air sensors and cleaning them too. Saw a forum on a ecoboost explorer that had surging that had a oily sensor
 

03'Darin

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Yes. Data logged again yesterday.

Ford has us looking at boost pressure, waste gate, MAP sensor and throttle body pids.

All of them showed the issue on each individual graph. The graph for the MAP sensor showed a jagged line which indicated the sensor was indicating small abrupt changes up and down. Hotline feels it indicates a bad MAP sensor

We ordered a sensor today and it should be here tomorrow.

I'm curious how much oil we'll see on it.

If the sensor gets here tomorrow we'll install it and I'll go try it out.
 
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