MiniRam users with simular builds.
Thread Starter
Pro
Joined: Oct 2003
Posts: 550
Likes: 0
From: Hesperia California
MiniRam users with simular builds.
I am having a problem getting the motor to run properly and I suspect it might possibly be in the tune. The car runs eratic at an idle and while driving at a sustained speen, it seems to miss or sputter. The car accelerates hard and runs like it is supossed to under acceleration and WOT.
History on build., also see profile!
AFR 180 comp heads, zz409 tpis cam, MiniRam, Tpis headers, 1.6 roller rockers, level 5 tpis chip, new bosch 24 lb injectors. Magnaflo cat back system.
I had it at a shop and they said everything checks out and the car is going into closed loop when it is supposed to. They believe it is in the fuel flow controlled by the computer. I have been in touch with Jim at TPIS and he said to have a tech call him if their any questions on the chip.
My problem is finding some one who dynos, and works on and tunes these type of computers.
History on build., also see profile!
AFR 180 comp heads, zz409 tpis cam, MiniRam, Tpis headers, 1.6 roller rockers, level 5 tpis chip, new bosch 24 lb injectors. Magnaflo cat back system.
I had it at a shop and they said everything checks out and the car is going into closed loop when it is supposed to. They believe it is in the fuel flow controlled by the computer. I have been in touch with Jim at TPIS and he said to have a tech call him if their any questions on the chip.
My problem is finding some one who dynos, and works on and tunes these type of computers.
Safety Car
Joined: Feb 1999
Posts: 4,724
Likes: 16
From: Little Elm TX
Many years ago, I worked a bit with a gentlemen named Ron Zimmer who used to own a company called Z-Industries in Southern California, he was one of the best at tuning TPI motors in the country at the time, including early ecm's.... I assume he still is, but don't know. It was hard to get him motivated, but when you did, he'd get it running right.
I do not know if he still owns and runs Z-Industries, but below is the link, I recommend you find out...... If he does, then you guys in socal have a very good resource right there in your own backyard.
http://www.z-industries.com/
btw, with your tpis stage 5 chip, I used to run one and still own one..... you gotta fiddle with timing to get it running right... or at least I had too. But, your problem could be a lot of things.
good luck !
I do not know if he still owns and runs Z-Industries, but below is the link, I recommend you find out...... If he does, then you guys in socal have a very good resource right there in your own backyard.
http://www.z-industries.com/
btw, with your tpis stage 5 chip, I used to run one and still own one..... you gotta fiddle with timing to get it running right... or at least I had too. But, your problem could be a lot of things.
good luck !
Last edited by Beach Bum; Apr 17, 2009 at 01:51 AM.
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Russ, look up LongBeachL98, he has a guy out here who is a wiz with OBD1 tuning. Does lots of C4s and Fbodys. Honest and reasonable.
Ill have to look for the guys name, havent spoken with him in awhile.
Bet you just need a good tune.
Ill have to look for the guys name, havent spoken with him in awhile.
Bet you just need a good tune.
Safety Car
Joined: Nov 2004
Posts: 4,991
Likes: 5
From: The Pines South Jersey
One of my East Coast racing buddies has a close combo to yours, send a pm to Vic89 amd ask him his #'s for fuel pressure, timing, idle rpm and tps voltage.
My m/r'd 383 has some issues that could be described like you did with yours, Russ said -"The car runs eratic at an idle and while driving at a sustained speen, it seems to miss or sputter. The car accelerates hard and runs like it is supossed to under acceleration and WOT."
Mine hunts for its target idle - the IAC over shoots high and low on warm up
Mine falls on its face when you jab the throttle - in park and in gear -
I found a dyno near me, I think I can get it resolved in a couple hours on the rollers
My m/r'd 383 has some issues that could be described like you did with yours, Russ said -"The car runs eratic at an idle and while driving at a sustained speen, it seems to miss or sputter. The car accelerates hard and runs like it is supossed to under acceleration and WOT."
Mine hunts for its target idle - the IAC over shoots high and low on warm up
Mine falls on its face when you jab the throttle - in park and in gear -
I found a dyno near me, I think I can get it resolved in a couple hours on the rollers
Instructor
Joined: Feb 2001
Posts: 211
Likes: 0
From: Chicago ILL
Sounds to me like you're experiencing a lean miss. The idle should be able to be cured with more timing and a little more fuel. This is what I did to help mine.
Last time I went to the emissions check station, I had my "lean" program in and the car runs absolutely terrible. Passes the test but the lean condition makes driving a chore.
If you know anyone who has a wideband O2, get your hands on it or just buy one. This is an invaluable tool.
BTW - The MiniRams love aggressive timing for best full throttle performance. I run 38 degrees total on my 406 with 11.0-1 compression.
Last time I went to the emissions check station, I had my "lean" program in and the car runs absolutely terrible. Passes the test but the lean condition makes driving a chore.
If you know anyone who has a wideband O2, get your hands on it or just buy one. This is an invaluable tool.
BTW - The MiniRams love aggressive timing for best full throttle performance. I run 38 degrees total on my 406 with 11.0-1 compression.
Le Mans Master
Joined: Feb 2005
Posts: 5,146
Likes: 3
From: The Motor City
At the most the only advice anyone can give will be an educated guess. What you have described can be a couple of things, typically their tunes are very rich overall.
The best advice/solution is to know exactly what is going on while the car is running. Download some software, buy a cable to interface a laptop through the ALDL to the ecm, and record the data. This in turn can either be given to a tuner to make adjustments or DIY. I believe your stage 5 chip comes w/re-tuning, provided you can supply data/logs.
The best advice/solution is to know exactly what is going on while the car is running. Download some software, buy a cable to interface a laptop through the ALDL to the ecm, and record the data. This in turn can either be given to a tuner to make adjustments or DIY. I believe your stage 5 chip comes w/re-tuning, provided you can supply data/logs.
Thread Starter
Pro
Joined: Oct 2003
Posts: 550
Likes: 0
From: Hesperia California
One of my East Coast racing buddies has a close combo to yours, send a pm to Vic89 amd ask him his #'s for fuel pressure, timing, idle rpm and tps voltage.
My m/r'd 383 has some issues that could be described like you did with yours, Russ said -"The car runs eratic at an idle and while driving at a sustained speen, it seems to miss or sputter. The car accelerates hard and runs like it is supossed to under acceleration and WOT."
Mine hunts for its target idle - the IAC over shoots high and low on warm up
Mine falls on its face when you jab the throttle - in park and in gear -
I found a dyno near me, I think I can get it resolved in a couple hours on the rollers
My m/r'd 383 has some issues that could be described like you did with yours, Russ said -"The car runs eratic at an idle and while driving at a sustained speen, it seems to miss or sputter. The car accelerates hard and runs like it is supossed to under acceleration and WOT."
Mine hunts for its target idle - the IAC over shoots high and low on warm up
Mine falls on its face when you jab the throttle - in park and in gear -
I found a dyno near me, I think I can get it resolved in a couple hours on the rollers
You might be closer than you know. I talked with Jim at TPIS today and ran it down to him what the car is doing. He suggested resetting the TPS to .62 from the stock .54 and setting the fuel pressure at 45 psi with the vacuum disconnected and then connect the vacuum. He said that stock 6 degrees btdc was a good starting place.
I think I am going to pick up a new TPS just becuz.
Hitech 5
That is interesting, and I will look into that.
Thanks to all for responding! I will keep you posted.
Safety Car
Joined: Apr 2002
Posts: 3,531
Likes: 1
From: Conroe TEXAS!
Cruise-In X Veteran
Im having the exact same problem. Idle can sometimes be goofy, and it feels like it has a stumble or light miss under very light throttle. Which means it runs like crap at crusing speed (55). Anything 1/8 throttle or more and it runs great.
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Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
Some light reading
http://www.thirdgen.org/techboard/po...31-post44.html
http://www.thirdgen.org/techboard/po...81-post48.html