Bogging and surging while cruising.
Greetings, my first post, although I have been lurking a bit reading up. I have a fresh install on a 94 351W aluminum 180CC heads and Trickflow stage one Cam. from day one she starts up like a champ and settles in to a nice idle. Early on in a cold start she likes to surge a little and I have notice that the RPM jump and occasionally will spike from like 800 to like 4443 but just for a second. The problem is during cruising and on a fact accel. During cruising it definitely is surging while driving at a stable speed regardless of speed. If foot is place to gas in a sudden mannor it bogs sometimes pops and stumbles. It eventually does recover and will get up to speed. Any help is appreciated. Cheers from Wyoming.
The great thing about EFI is that we have the ability to look at and record data. Learn to datalog. Fitech website has a good tutorial on the process. Share the file here with a Dropbox or Cloud link. We will start there.
I want a 30 second datalog of idle only. Verify that the temp sensor is reading above 170 degrees. Tuning and logging is useless, if unit does not see 170 degrees.
Are you running timing control?
Also describe your fuel system. Do you have a fuel pressure gauge.
Roger will get a log on. Fuel System I have an inline pump was previously running stock intake 80 injectors and powerdyne supercharger. So I know the pump can keep up. it is the stock mustang tank and a return line has been added.
Also no timing control.
Ok I hope the log is what you were asking for. She was a chugging and bucking for about 3-4 minutes and then settled in ok. I did notice the IAC warm were just a touch high. Fuel pressure going into the Fitech unit was right at 55#
https://drive.google.com/file/d/0B6oicPxOWUn3WnRnTjhsMkp5dzdhZ3RKM25oRGFBRGZFRWY4/view?usp=sharing
You have 76 fault code. I believe that is O2 code. Could be wrong. Your target AFRs arent changing, but your Trims are big. What is your cam setting and cam specs? Also, do you have a minimum of 18 in exhaust past O2 sensor?
There is at least 18 inches of pipe behind the o2 sensor.
currently have the cam set to 2 and the specs are
Cam Specs
2,000-5,500
Intake Duration at 050 inch Lift: 221
Exhaust Duration at 050 inch Lift: 225
Duration at 050 inch Lift: 221 int./225 exh.
Advertised Intake Duration: 275
Advertised Exhaust Duration: 279
Advertised Duration: 275 int./279 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.499 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.510 in.
Valve Lift with Factory Rocker Arm Ratio: 0.499 int./0.510 exh.
Lobe Separation (degrees): 112
Camshaft Gear Attachment: 1-bolt
Computer-Controlled Compatible: Yes
Grind Number: HR-224/339-2S-12
Valve Springs Required: Yes
Lift w/ 1.6 rocker (intake/exhaust) - .499"/.510"
Lobe separation (degrees) - 112°
Does look like an O2 error code Ill see if I can check the connection tomorrow