Two questions about hard core wrong gas.. and noise :)

[Window45]

When i gun my car it feels, what's the word.. it kinda feels ruff in the gas peddal area just seeing if anyone else has this problem. also when i get up on it, i literally sounds like the car is gutless? i mean i would think from this 4.5 monster id get some power all the way up the rev line... again this was me using 87 octaine gas... does the gas you use REALLY have a factor in power with the vh45de engine?

[goody90q45]

Welcome to NICO. Octane does matter. Put some premium in your tank the next time you fill up and you'll feel the difference.

A little more maintenance history is in order. Mileage, repair work (i.e. fuel pump), check engine light (CEL) on, service records? You've probably got more going on than just low octane fuel. When you get a chance take a tour of the Q45.org website, especially the Tech Help section and you'll learn a lot about your Q. Good luck.

[maxnix]

Really, if it is not in as new condition less normal well maintained wear, it is difficult to tell what is wrong.

Running less than 91 octane gas is owner abuse. Pray that prevous owners were not also abusers!

[jimbyjimb]

Get a FULL tank of 91 or 92 octane. After using 91/92 for a couple fill ups report back if there is any difference in power output. If not, you know the gas is not the problem.

[gammer_ghn]

lol wait for it the flames of you not using 91 gas will get you !

[Mopar]

lol wait for it the flames of you not using 91 gas will get you !

Yessiiirr!!!!! (btw whatsup man?)

I landed my car to my mom for a day and she wanted to be nice so she filled it up full tank of 87. Needless to say it was NOT needed!

[maxnix]

I landed my car to my mom for a day and she wanted to be nice so she filled it up full tank of 87. Needless to say it was NOT needed!

Doesn't it say "Premium Only" by the fuel filler door?

[gammer_ghn]

Holy old friend bat man! How you been bro? I haven't seen you in ages... You fix your car yet?

[MinisterofDOOM]

again this was me using 87 octaine gas... does the gas you use REALLY have a factor in power with the vh45de engine?

Absolutely.

The gas you uses has a factor in MORE than just power. Using poor gas or low octane can DAMAGE an engine. Especially if you have bad knock sensors. Higher octane gas is more difficult to ignite. The harder it is to ignite, the more compression it can take. If you use low-octane fuel in a high-compression engine, it'll ignite without need for spark (just like a diesel). And when that happens, it can cause damage in addition to inefficient burn (which means less power). That's why cars have knock sensors: to prevent this from ever happening and prevent the damage.

If you use 91+ you'll get more power, treat your motor better, and will likely get better fuel efficiency than lower octane. Also worth noting is the fact that many gas station brands only put detergent in their premium fuel, so you're missing another benefit of premium if you fill up at those places (Chevron puts techron in all 3 grades, so that doesn't apply there).

It's definitely WORTH (and not merely a good idea) upgrading to premium with the Q.

If you were just driving an average-compression econocar, premium would probably be a waste (aside from detergents, which you can buy separately if you need) since lower octane fuel DOES contain more latent energy. But that energy can't be used as effectively in high-compression motors, so it becomes irrelevant in those cases.

[northt]

Isn't the default on bad knock sensors to retard the timing 5 degrees? Seems like that would maximize the car's ability to adjust to low octane fuel...

[Window45]

ok guys.. well i filled er up with 91 octaine.... lol it's been so long since i been using it... wow i get much better mileage and much more power.. i just ment, like i had the waterput go out.. ok so i had a new one put in, then one night, i decided to push the car a bit (it wasn't drove for a few weeks prior to the waterpump) so i got on it on a freeway, and then it felt like .. just horrible you could feel the car having a horrible time, it still performed but it ended up blowing the filling around the waterpump sooo i dunno, that's all fixed though... i also have a small vibration in the rear of the car when i going from 2nd to thrid... what would cause that?

[Kiven422]

I once put Regular 87 gas (full tank) in my Q although it was on top 1/4 Premium 91.

Symptoms - My car always has had 91. After that 87 tank I went back to putting 91. Within 2 weeks (prolly after 3 91 fillups) my car had a bad hesitation. It never felt that way ever. I'm sure it was because of the regular gas.

Results: With 87 I got MUCH better mileage! With 91 I'm very lucky to hit 100 miles per 1/4 tank. With 87 I was pushing past 115-120 miles per 1/4 tank. I count my mileage at every fillup. It wasn't as powerful but I still beat an older trans am from 70 up to 135mph without having to switch down to 3rd gear.

It ran well throughout the 87 tank... just one bad hesitation during the 91 tank after that. My car never hesitated.

My conclusion - don't fill lower than 91.

[jimbyjimb]

Fact is, computer controlled engines are tuned to operate with a certain octane fuel, using premium in a car meant for 87 can be equally as damaging. The sad part is there are alot of people out there thinking they're being good to their cars by putting preemo in when 87 is called for, and are destroying the engine's internals. Lower octane burns faster than higher octane, and in the day of non-computer controlled vehicles when the engine tuning parameters were set by hand timing could be advanced or retarded at any time to adjust for whatever fuel you would wish to use. In today's world of smarter controllers alot of computers can adjust for this, but, especially in the 90's, most computers will not adjust for different burn rates and this is damaging. Unless your car is modified use manufacturer reccomended fuel grades. The manufacturer sets specifications for a reason, specifications that should not be ignored unless you are proficient in the understanding of automobile functionality, or unless you want to hinder your cars performance in some way.