my car randomly "bucks" every once in a while. I have a feeling it has something to do with the HKS SSQBOV i just installed, could that be what is causing the bucking??? Chime in anyone! (oh, and even under the bucking every once in a while, the A/F ratio is still fine) so ionno....

 

When you say bucking are you referring to a violent jerking back and forth that the entire car is making? Please explain in more detail Im sure we could find an answer

 

It seems like.....Ok, ill be driving and at random rpms and it will seem like there is a loss of fuel or something, and then it will start driving again but make a very quiet popping sound, as if it were spitting (so the car will be moving, then cut out, then move again)...problem is, i have narrowed it down to a few things....1) i dont THINK its a loss of fuel because my A/F ratio is fine 2) its not misfiring because im not getting a CEL 3) Its not my engine reading boost because i just replaced the little synapse filter thing....this is getting annoying because it will only do it sometimes and i cant quite figure it out.. BUT, imma check and see if it is the BOV and if it isnt, then im just gonna buy a damn AEM EMS and get it tuned( i have 750cc injectors on the way as well as the AEM FPR) ....this is just weird (Although it didnt seem to do this when i had a different BOV on the car...thats the only reason i think it is that...) Chime in if you think you might have a suggestion.

 

Do the rpms change when this happens? If so what do they do?

I had a similar problem in my gsxr... If I cruised t a certain rpm the engine would abruptly die, restart and continue the cycle until I changed the engine speed. Turned out that at the one spot in the rpm range I would hit the right harmonics to kill my kickstand switch, but I doubt that is your problem

 

the rpms don't change really. I took my brother in the car with me to show him. He said that at wot the a/f was around 11.5 and from 8-9k went to 13 or so, but he said when i was just crusing the a/f was at 14.7ish. I know the idle should be that but even when i am crusing?? Also i put 1 step colder plugs in the car. Could this be a problem. Everything is basically back to stock with the bov except i put 1 step colder plugs in the car and i dont think it matters but the after market fuel pump came with filter that kept getting stuck at the 1/2 tank mark so we put the stock filter piece back in the tank. I cant seem to figure out what the problem is. Could the plugs really be the problem or the stock fuel filter paper? Thanks again guys

 

I have been talking to my bro and we both have figured that the problems started 2 weeks ago, about the exact time I installed the colder plugs. So tomorrow we are going to reinstall the stock plugs and see if this stops the problem. I am not sure if it is the colder plugs, the colder air from the night and other factors have anything to do with the issue but I have noticed that it started to do this 2 weekends ago on a trip to the beach and im almost certain I installed the plugs the Friday before we went to the beach. Hmmm, could a plug gaped wrong do this. So far i think that after just cruising and not pushing the engine it may just not be burning hot enough. Again, input would still be greatly appreciated.

 

It is really hard to tell you anything thru internet(especially noise sounds). Maybe knocking or bad inj? Idk. Should check with local guys or tuner.

 

I once had bad bucking with corroded connections on my AEM ecu. Let us know what you find out. In future give us a full mod list, it would be very helpful.

 

Yea, Imma try to put on my other spark plugs, if that doesnt work, do you guys think it could be that i had to put on the Stock Fuel Filter on the walbro 255 because the filter the walbro one came with was hitting my gas measurer so i just threw the stock filter back on (but i dont see why that would matter, its just a filter).

 

Try plugs first, don't bother with Fuel Filter. If your blowing out the spark, or gapped wrong for what your doing it could cause problems that wouldn't show up in AFR. What are your mods and what exact spark plug and gap are you running?