1995 pinging continued
Thread Starter
Instructor
Joined: Jun 2000
Posts: 171
Likes: 1
From: Chicago
New PCM tune solved it. I did have to adjust the throttle plate stop screw to bring idle up a bit. It had no plug and judging how easy it turns it had been messed with by last guy. After doing that, reseting IAC, idle is great and the car seems to be running perfect after a few on and off cycles and different driving scenarios. Despite my best efforts, no pinging and it is downshifting now like I thought it should have before.
Have to wonder if I ever needed EGR, O2's and other stuff but it was all good stuff to do based on age anyways.
Have to wonder if I ever needed EGR, O2's and other stuff but it was all good stuff to do based on age anyways.
Thread Starter
Instructor
Joined: Jun 2000
Posts: 171
Likes: 1
From: Chicago
Yes and when I replaced the EGR it was some no name non original one and pretty cruddy. For only 40,000 miles someone had been in there and played with that too. I just had to undo the previous mess basically.
My guess, when the throttle body was powdercoated they removed the plate stop screw and who knows where it was set actually. Out of dumb luck I just have it set right now, I could probably knock another 100RPM off the idle speed but I am leaving it!
Problems like this teach you a lot about the car if you stick with them, thats for sure. I could use a break though!
My guess, when the throttle body was powdercoated they removed the plate stop screw and who knows where it was set actually. Out of dumb luck I just have it set right now, I could probably knock another 100RPM off the idle speed but I am leaving it!
Problems like this teach you a lot about the car if you stick with them, thats for sure. I could use a break though!
Thread Starter
Instructor
Joined: Jun 2000
Posts: 171
Likes: 1
From: Chicago
Well I'll be. After returning my old PCM to the tuner and descrinbing to him how I had to force the idle with throttle plate he took a look at it. He traced it back to a good local tuning shop where he actually used to do their OBD1 tuning, though not this one, said it was done about 4 or 5 years ago near as he coudl tell.
Turns out my car has more work than I thought. I have an LT4 hotcam or something similar and tuned for 30lb injectors. On closer inspection I do have Ford Motorsport 30lb injectors after I sent him a picture of them. My idle was indeed set a bit higher than stock at 775 on old ECM explaining why that went a bit hay wire when he sent me a new tune with stock idle parameters.
Long story short, he was surprised my car is running as well as it is with the current tune but he is currently flashing the ECM and sending me the right one. Wow! I knew this car felt faster and idled a bit different than a 96 I had like 10 years ago and now I know why.
So I will now have the proper tune to match this beast and more power.
Turns out my car has more work than I thought. I have an LT4 hotcam or something similar and tuned for 30lb injectors. On closer inspection I do have Ford Motorsport 30lb injectors after I sent him a picture of them. My idle was indeed set a bit higher than stock at 775 on old ECM explaining why that went a bit hay wire when he sent me a new tune with stock idle parameters.
Long story short, he was surprised my car is running as well as it is with the current tune but he is currently flashing the ECM and sending me the right one. Wow! I knew this car felt faster and idled a bit different than a 96 I had like 10 years ago and now I know why.
So I will now have the proper tune to match this beast and more power.
Last edited by C4GUY; Nov 16, 2011 at 08:11 AM.
Thread Starter
Instructor
Joined: Jun 2000
Posts: 171
Likes: 1
From: Chicago
Hopefully closed out, new and proper PCM should arrive tomorrow or next day. I kept rambling in this thread more for information purposes as I went along. So many threads die off just when you think they are getting to the answer. Believe me after reading 3,567 threads on idle speed I found this out.
Other lesson learned here is I did take a relatively systemtic approach at each step rather than just throwing parts at it. The biggest of which being once I had all sensors up to snuff and replaced due to age I knew I had to remove the one unknown the PCM tuning before going any further and that did it. I could argue I should have done this or that 1st, but I took each step and learned something new.
And one more thing I learned, we need to separate LT1 and L98 into separate areas. Too much confusion.
Other lesson learned here is I did take a relatively systemtic approach at each step rather than just throwing parts at it. The biggest of which being once I had all sensors up to snuff and replaced due to age I knew I had to remove the one unknown the PCM tuning before going any further and that did it. I could argue I should have done this or that 1st, but I took each step and learned something new.
And one more thing I learned, we need to separate LT1 and L98 into separate areas. Too much confusion.
Last edited by C4GUY; Nov 16, 2011 at 02:40 PM.
Le Mans Master
Joined: Jul 2009
Posts: 6,381
Likes: 66
From: SF bay area C.A.
C4 of the Year Finalist
HA HA the LT4 hotcam was a big surprise I'l bet. Someday I need to start checking some #'s because mine seems to be unusually quick. Just need to keep the tires flat on the asphalt.
Last edited by kimmer; Nov 16, 2011 at 02:59 PM.
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Thread Starter
Instructor
Joined: Jun 2000
Posts: 171
Likes: 1
From: Chicago
It is a surprise, can't be sure it is a hotcam but based on tune it is or something very similair. Also discovered the needle bearing style roller rockers looking through oil filler cap. Last owner was a bit coy apparently when I asked have you ever opened the engine besides the bolt ons. For all I know it has head work too but we'll never know.
Thread Starter
Instructor
Joined: Jun 2000
Posts: 171
Likes: 1
From: Chicago
Newly programmed PCM is in and perfect! I did not know how good this car could feel. No bogging or pinging like it used to do under that light throttle application. Idle is perfect. Downshifts nice and feels more responsive all around. On datamaster; IAC counts, fuel counts etc are all great.
