Car Jerking

[mspzehren]

When i try to accelerate kind of fast almost every time, in like 3rd gear and up my car will like hesitate to accelerate then jerk hard and then continue accelerating, also on the highway when im cruising an easy 65 and i push the pedal down it does the same thing.. anyone know whats wrong?

 

[haveahotcarl]

When i try to accelerate kind of fast almost every time, in like 3rd gear and up my car will like hesitate to accelerate then jerk hard and then continue accelerating, also on the highway when im cruising an easy 65 and i push the pedal down it does the same thing.. anyone know whats wrong?

Fuel cut? Any mods? Have you gotten the factory ECM re-flash?

 

[ohdavy1]

Your feeling hesitation, due to the fuel cut, very common. Could be heat soak, etc. I have found a little fuel injector cleaner with a fill up can sometimes help the issue

 

[mazdaspeedp]

maybe replace ur spark plugs it will help a bit

 

[heckaTIGHTis]

I'm having the exact same problem (completely stock car, 120k). I notice that it doesn't usually happen until around 5 minutes after I start the car. Only happens above 3k. I'm going to change the plugs myself this week. Will going with 1 step colder plugs make any difference in a stock setup?

 

[orng1]

I bet you have a leak somewhere in the charge pipe. Your over spooling and losing boost somewhere. Check all the charge pipes, anything after the MAF.

Welcome guys. (hi)

 

[krayzedpinoy]

That happens in my car. I have new NGK spark plugs and Magnecore competition plug wires so my ignition is fine. Upgraded my fuel injectors, not only cleaner but larger, and I have an O2 signal modifier which prevents my stock ECU from reading too rich so it'll be like "WTF" and keep giving fuel at WOT. I stopped running lean, but other than that I still get the fuel cut... hmmm... oh, and underboost I don't loose pressure.
I think mspzehren's problem and mine might be similiar.

Any other thoughts that might help?

 

[orng1]

Well the maf controls fuel cut so your maxing that out.

 

[mspeedprotege]

ive got the same problem. as soon as i upped my boost my car has never ran the same. even after i set it back to the factory psi it still hit fuel cut and hesitates... i feel the only way to fully fix it is with some kind of engine management. i really wana get the slit second tuner... anyone have it?

 

[krayzedpinoy]

ah, bummer, I guess it's time for me to spend more money >.<

 

[orng1]

ive got the same problem. . i feel the only way to fully fix it is with some kind of engine management. i really wana get the slit second tuner... anyone have it?

Adding more variables to your problem is a bad choice, the MAF is being maxed out and that's most likely the reason your hiting fuel cut at stock boost and having hesitation. It'll just add fuel if you have a leak after the MAF. Get it right first then add a few more parts for power. You'll have a much better running car and you'll be glad you did that over blowing your engine. Good luck everyone.

 

[heckaTIGHTis]

Is it possible that it could be just a dirty MAF sensor?

 

[mspeedprotege]

it seems like ever msp owner has had this same problem even after checking to make sure there arent any leaks, and after getting the ecu update. the only guy i know who got rid of the problem was after adding the slit second. i feel like this is more of a computer problem than a machanical problem, after seeing it on so many speeds all with different mods including stock. maybe theres is a maf problem that mazda never did anything about, or maybe mazda took to many extra steps to make sure you have plenty of fuel even if it means to much and hitting fuel cut... who knows

 

[orng1]

The only times I have had any serious hesitation was when I had a leak. After relocating the MAF that went away and if I ever had a leak the car just felt slow or the turbo sounded loud. I could tell exactly what the problem was, though it still drove well.

Maybe I'm wrong but I think I have had a little more experience than most of you guys. The only times I have had issues is when there was a leak. The stock pipes suck balls and I never had any issues after replacing the stock pipes. I've had 4 MSPs and they all have the same issues. WGA, leaky pipes, bad LSD, and the mid pipe break. Not all of them had every issue but you see it pretty often.

 

[heckaTIGHTis]

After some investigation, I found this:

It looks like the p.o. might have had a gauge connected, but it's gone now. Also when I went to clean the MAF sensor I noticed that one of the screws is missing, and I wasn't able to remove the sensor because it was in there pretty good and I didn't want to damage it. The hose connected to the filter housing was VERY loose and it wasn't on all the way, so it may have been leaking from there although I don't know for sure because I haven't driven it since. This picture is from AFTER I tightened it.

 

[mspeedprotege]

orng1 did the problems go away after you relocated your maf? ive been wanting to get hard pipes but i didnt want to spend the money to only later get the fmic kit that comes with them. i didnt want to buy and install the fmic with problems . i wanted the car to be sound before adding anything else.

 

[heckaTIGHTis]

orng1 did the problems go away after you relocated your maf? ive been wanting to get hard pipes but i didnt want to spend the money to only later get the fmic kit that comes with them. i didnt want to buy and install the fmic with problems . i wanted the car to be sound before adding anything else.

The Turbbohoses kit comes with the piping AND the intercooler? I thought you had to buy both of them (spin) Unless you're talking about a different kit, or I'm wrong

 

[mspeedprotege]

i just saw a complete kit. i didnt price out everything but im thinking its cheaper for the hole kit idk im more worried about my frozen front right caliper than how my cars running right now

 

[asdflovejkl]

hey new here(hi), i have the same problem on my stock msp the hesitation is around the beginning of the 3k rpm up to 4k, the hesitation lessens when i brought the boost back down from arnd 5 to maybe 1psi, i've heard its the fuel cut and the ecu reflash could help but i also heard the reflash is no good if you plan on increasing the boost....hella confusing...tempted to reflash it since i'm not getting the fmic any time soon...

 

[orng1]

orng1 did the problems go away after you relocated your maf? ive been wanting to get hard pipes but i didnt want to spend the money to only later get the fmic kit that comes with them. i didnt want to buy and install the fmic with problems . i wanted the car to be sound before adding anything else.

Do a fmic kit, it solves a lot of problems in one kit. The stock plastic pipes are crap, the interwarmer is what it is, the plastic pipes have leaks and break. Don't hesitate just do it.