Konstantine16

I cannot remember when this started happening or if im just noticing something normal but this has worried me lately. When im in gear (any gear) cruising and just slightly pushing the gas pedal to keep the car coasting, the car begins to make a jerky kind of movement forward and backward, similar to what happens when someone does not know how to drive stick but not as bad. It stops doing this when rpm rises above 2000 but if I have the rpm below 1800 it starts to do it again. It does this still when the engine is up to temp and does it if im in any gear and the rpm is in the range I mentioned. The car is full bolt ons with a 228r cam and stock untouched heads. It has a street tune. Any thoughts or comments on this would be greatly appreciated!

tdevil55

iTrader: (23)

Check your MAF. Could be dirty, or failing. Mine did that with a aftermarket MAF on. I switched it back to a stocker and it quit the serging/lugging that you explained.

Konstantine16

hmm interesting. I still have the stock maf but have been using a K&N filter so I wonder if the high pollen level around here +humidity could be doing it, im gonna use some maf cleaner on it tomorrow and then make another post on whether it helped or not.

wssix99

iTrader: (5)

If your MAF is fouled, its probably due to the K&N filter itself. It can shed oil off, which contaminates the MAF. The MAF has a heating element on it, which will burn off pollen, water, etc. but it can't handle oil.

I had severe MAF issues, lost my K&N, and went back to paper. Life has been great since.

Konstantine16

while cleaning my maf I noticed it had no screen on it so that probably didnt help.

wssix99

iTrader: (5)

Its there mainly to protect the fragile elements inside. If there's damage, you should get a code back when scanning.

Konstantine16

My service engine light turned on last night and im getting this code: P0704 clutch input circuit malfunction. how are you supposed to fix this? I wonder if this is the cause of my clunking and lugging?

wssix99

iTrader: (5)

Could be. Its probably a bad clutch pedal switch. If you take off the lower IP cover, you should see it up under the dash attached to the clutch pedal. http://www.gearchatter.com/viewpost13542.php

nascarnut08

AMSOIL offers an air filter that filters smaller particles than a K&N and it is a dry filter. The AMSOIL Ea Air filter is good for 4 years or 100,000 miles. To clean, just use shop air or a vacuum. No need to buy oil charge kits and wash and recharge. Just a thought!

Konstantine16

Had the code deleted and it never came back. The shop I take my car to said it was because of the tick master cylinder I had installed a while back. Car still lugging and not riding smooth below 1800 rpm its annoying as ****. If a cylinder was not firing in my engine it would be throwing codes right?

tdevil55

iTrader: (23)

In theory, yes, a code should be there, but we all know that they don't always present themselves till its either too late, or they throw one that we say "WTF does that mean". See if a bud has a MAF you can use to test to see if its your MAF causing this. Only other thing I can think of is doing a test on the fuel pressure. Get a tester, make sure its the one with the long hose, and tape it to the window and take a test drive. Watch the PSI when the car lugs again and see where its at (watch it not want to lug when your testing it ). Could be loosing your pump or that its not giving enough psi at that low of RPMs and is causing the car to lug or try to stall (just a shot in the dark on this one). I still think its in your MAF, cause this is what mine was doing and thats how I fixed it.

matt1289

I am having the same issue. I cleaned my MAF with that electronics parts clean stuff that didnt really help. Let me know what you find out I was thinking it could be my Fuel pump but I remember replacing my MAF a while(3 or 4 years ago when I first got the car) back and it was doing something similair to this. I don't really know anyone in OKC with a car like mine or I would swap that MAF.

Let me know what you find.

Konstantine16

The fuel pump is a recently installed walbro 255L that was installed to help with the cam. I am going to try replacing my in-line fuel filter, along with swapping the maf and see what comes of it.

matt1289

any new info did you end up fixing it or no?

intense3123

Had this same problem when cruising in 6th gear at very low rpms. replaced spark plugs and it went away.

Konstantine16

I never got around to the maf swap or anything and the problem still comes and goes. Sometimes it will drive fairly smooth and then it will start jerking around again if i get below 1500 rpm. I hope its not the plugs because I just bought a new set not to long ago

rabbit320

iTrader: (11)

how about sensors? o2's?? same thing with mine, im still trying to pinpoint it... gona try cleaning my o2's soon... oil change helped tho...

matt1289

I just got a new MAF I seem to get better mpg and runs a little smoother. My car still jerks at low rpm and with cruise control on, it runs really stong above 2,500 rpm, but not anything below that. It also will act like it is about to stall then all the sudden all the power is back all at once. I can't figure it out.

I have 0 codes poping up
I have a brand new MAF 1 week old
o2 sensors are less than a year old I guess I willl try cleaning them
Runs perfect until it goes above 100 deg. Thats telling me it's some sensor somewere just got to find it.

marksboy7

iTrader: (6)

Carefully check all your plug wires. My truck was doing the same thing it sounds like and come to find out I had a cracked plug wire where it had been burnt through from resting on the headers.

matt1289

I've checked my plug wires, there new and the 2 center ones on each side have the heat shields.