Problem since miniram install
Thread Starter
Intermediate
Joined: Jun 2007
Posts: 41
Likes: 1
From: St. Louis Missouri
Problem since miniram install
Long story short, installed miniram on a 1990 convertible 134,000 miles. I am shure there are no vacume leaks, distributer is in right/timing is correct/damper has not slipped. There are no codes. Fuel pressure is correct. This is what the car is doing. Sounds like there is a miss, and when driving the car backfires, stumbles, etc.. Full tuneup was performed right before mini install, new injectors installed(had multitechs) allthough they they all ohmed out at a good value. What should I look at next? I am trying to get a scanning device also.
Race Director
Joined: Jan 2008
Posts: 16,028
Likes: 170
From: oregon
timing or the distributor is a tooth off. normally a tune would be a good idea since the car will be rich in the lower range due to the slower airspeed of the mini but it should not be causing anything that big. check the dist & timing.
Last edited by racebum; Jun 15, 2008 at 11:22 PM.
Thread Starter
Intermediate
Joined: Jun 2007
Posts: 41
Likes: 1
From: St. Louis Missouri
Thanks for the replys, I have a chip from pcmforless, with or with out the chip it runs the same. I also changed timing around just to see what it would do and had the same problems. After reading other threads and talking to Alvin at pcmforless I am going to keep it at 6 degrees BTDC.
Thread Starter
Intermediate
Joined: Jun 2007
Posts: 41
Likes: 1
From: St. Louis Missouri
Ok, I was able to borrow a tech 1 the other day and the only problem I saw was the TPS at full throttle was only at 4.16v, idle was good at around .54v. The FSM says full throttle should be at 5v +-.5 , so could the lower full throttle voltage cause a problem?
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Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
On $8D it doesn't really matter. It will trigger PE at 70% of throttle, which is 70% more than whatever the voltage was at key on. Its a little smarter than early masks.
Your problem is $8D and a miniram. On $6E and $32B (maf) calibrations it almost works so/so, but on speed density the map won't trigger enough AE quick enough and you'll get a pop through the intake, a stumble, etc.
(i've only done this about a dozen times)
The miniram is like a singleplane, it wants TONS of AE. If you were doing your own chips I could tell you what tables to edit and an idea of how much to throw in, but it really needs to be driven, logged, tuned, logged, and repeat. You can't tune a car from a thousand miles away.
-- Joe
Your problem is $8D and a miniram. On $6E and $32B (maf) calibrations it almost works so/so, but on speed density the map won't trigger enough AE quick enough and you'll get a pop through the intake, a stumble, etc.
(i've only done this about a dozen times)
The miniram is like a singleplane, it wants TONS of AE. If you were doing your own chips I could tell you what tables to edit and an idea of how much to throw in, but it really needs to be driven, logged, tuned, logged, and repeat. You can't tune a car from a thousand miles away.
-- Joe
Le Mans Master
Joined: Feb 2005
Posts: 5,146
Likes: 3
From: The Motor City
You can't tune a car from a thousand miles away. Joe
Last edited by mseven; Jun 19, 2008 at 07:45 PM.
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
Hows the project coming?
I think out 'ac delete thread' died
Anyhow, yeah, he needs some tuning. I think a ton of AE will probably make it bareable, but overall someone needs to spend some time redoing the VE tables, then advance, then maybe VE again heh..
-- Joe
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
A short runner intake is a huge change
MAF systems are a lot more forgiving. A lot of people settle for 'its running fine' but in reality its a turd. This is probably why we see soo many expensive builds in the 13s when they should be deep in the 12s.
And don't even get me started on the guys who think all you need to do is raise fuel pressure and turn the dizzy.
-- Joe
Le Mans Master
Joined: Feb 2005
Posts: 5,146
Likes: 3
From: The Motor City
Hey Brother!
Hows the project coming? I think out 'ac delete thread' died
Anyhow, yeah, he needs some tuning. I think a ton of AE will probably make it bareable, but overall someone needs to spend some time redoing the VE tables, then advance, then maybe VE again heh..
-- Joe
Hows the project coming? I think out 'ac delete thread' died
Anyhow, yeah, he needs some tuning. I think a ton of AE will probably make it bareable, but overall someone needs to spend some time redoing the VE tables, then advance, then maybe VE again heh..
-- Joe
I was surprised to see that thread still lurking. I'm going through the steps myself (new Stewart cw. pump et all).
Yeah, I had some serious time in my tune before I could actually say it was done....of course, until the next drive
Even after I had the tune nailed, then it was working the mat v.s. mat stuff for temps. (now there is a fun table)....it never ends. Now I'm getting ready to start all over again w/the new one.My problem is, every time I drive the car the laptop is my only passenger, and is set-up w/emmu.
.
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
I'm gonna do the cluster in oct. That way if I run into problems I can push it on a trailer and forget about it until the spring.
-- Joe
Safety Car
Joined: May 2006
Posts: 4,290
Likes: 140
From: Salem NH
If you ever want to run map, I'll help you repin the harness but you'll lose your DIC. (mpg, range, etc).
-- Joe
