Chevrolet Cruze Forums banner
21 - 40 of 63 Posts

·
Registered
Joined
·
509 Posts
Dealer didn't find anything like I figured. It has been 100+ here for weeks. Car is a dog. There is a thread in the engine forum that talks about GM saying it really retards timing with 87 octane. I filled with 91 this time and will see if it helps any.
This is exactly what I was going to post... I also get the surging when it's hot out, and I've been sitting at a light (heat soaking the intercooler)... It does feel like it's sensing a detonation and pulling timing, then bringing it back, then pulling it, then bringing it back...

We got 35mpg on a 500 mile trip going mostly 65mph, on mostly flat-ish land... It was in the 90s, and we were running the A/C, though...

On the other hand, when I'm not running the A/C, and not being really nice to it, and it's 65F outside, I get 41-43 on my commute...

I tried to get in the gas heavily from like 1500rpm in 2nd gear the other day, and it literally fell on its face... It's pulling timing like crazy in this heat, with 87...

Going to run 91-93 for a bit, here, and see what we see...
 

·
Registered
Joined
·
119 Posts
Does anyone who is having this problem, have a tune installed? Any other aftermarket parts? The symptoms would indicate that the ECU is squirting more fuel than it should. Here are things to check:

HARDWARE:
Intake tubing, make sure all clamps are secure, no tubing collapsed, no holes or abrasions
Vaccum tubing, check for abrasions and leaks
O2 sensor...well this is more of a software item for end users, but if you want to ask the dealer to check it, might be helpful.

You can make an intake pressure tester with some pvc fittings and an air hose connector and pressure gauge. This will help you test your intake and vaccum plumbing. Here is an example: DIY Boost Leak Tester

SOFTWARE:
You need a OBD2 scanner with datastream capabilities to diagnose these.

FUEL TRIMS, very important. The ECU has Long Term and Short Term fuel trims. These are correction factors applied to the preset maps programmed into the ECU. The values are changed using sensor feedback, mainly from the O2 sensor. When you are in steady state cruise or light acceleration, the ECU is running in "open loop" mode, meaning it is using the O2 sensor to maintain a set air/fuel ratio (usually 14.7:1). Any corrections that need to be made to maintain the air/fuel (known as the "lambda" value) are shown in the fuel trims.

Ideally, your fuel trims should be within 5%. Any bigger deviation could indicate hardware or sensor problems.

KNOCK RETARD
This is the amount of ignition timing that is being pulled out due to the knock sensors detecting vibrations. On the 3800, there are at least 3 different spark advance tables (bad fuel, good fuel, mean best torque) and then the knock sensor retards timing from those preset values. If timing retard is significant and sustained enough, it uses the bad fuel table until it detects no more knock. Secondly, just because the knock sensor is reading, doesnt mean you are knocking. False knock can happen due to other mechanical noise, such as a heat shield banging on the engine block. Some ECUs will add fuel in an attempt to cool the intake charge when knock is detected.

Warning: If you are datalogging, please do it with a friend. Always drive safe!

If i think of something else, ill make another post
 

·
Premium Member
Joined
·
2,134 Posts
For all but one of you I have not heard any mention of the RPM band or driving conditions. If you are "jumping on the gas" below 2000 or so RPM the car is going to fall flat on it's face guaranteed because you have no boost. Having said that I see some of you are running 87, and it was touched already that in this heat 87 octane is not sufficient to have the car run properly.

Having said that my suggestions:
1. turn more RPM, if you are shifting below 2500-3000 with any kind of load you may end up in trouble and, believe it or not your gas mileage will probably improve if you carry more RPM. On flat roads or low load levels by all means shift early and keep the revs down
2. If it is hot where you are try higher octane
3. check for boost and or vacuum leaks if the dealer has already looked at it. Had a friend with a Cobalt SS with the same problem and it was a cracked intercooler pipe
4. data log, data log, data log! Find out what your sensors are saying then look up what they should be saying. If they are different you have leverage on the dealer.
5. Don't let the dealer tell you it is normal, if you are not happy it is up to them to make it better under warranty. If I were this displeases I would hand them my keys and say give it back when it runs right.
6. Test drive a new one, see if it acts the same way
 

·
Premium Member
Joined
·
2,134 Posts
Was reading some other threads and has anyone had their Catlytic converter checked? An obstruction in the exhaust would certainly cause these issues also
 

·
Premium Member
Joined
·
1,142 Posts
You're complaining about a lack of power and how slow the car is yet you claim you rarely rev the motor passed 2000 rpm? This isn't a big block that makes gobs of off idle torque, you've got to rev the motor up into its usable power band. Your motor is plenty capable of producing enough power to roll smoke off the tires all through 1st gear, you shouldn't have to worry about moving out into traffic...

I'm sure the hot summer weather has made the car feel a little slower than it did in early spring but you still need to wind the motor out if you expect the car to move.
 

·
Registered
Joined
·
151 Posts
You're complaining about a lack of power and how slow the car is yet you claim you rarely rev the motor passed 2000 rpm? This isn't a big block that makes gobs of off idle torque, you've got to rev the motor up into its usable power band. Your motor is plenty capable of producing enough power to roll smoke off the tires all through 1st gear, you shouldn't have to worry about moving out into traffic...

I'm sure the hot summer weather has made the car feel a little slower than it did in early spring but you still need to wind the motor out if you expect the car to move.
Good points... I keep it below 2500rpm for normal driving, but if you need to accelerate, like on an on ramp or something, don't be afraid to wind it up a little. Once the turbo picks up some speed, the car will really move. Plus if you're fortunate enough to have your windows open, you're rewarded with the beautiful sound of the turbo spooling up. :wub:
 

·
Registered
Joined
·
61 Posts
Discussion Starter · #32 ·
Yeah sorry. I traded in a cammed, headered, full bolt on 2005 Mustang GT. My toy Mustang had a 12:1 compression 514 inch motor with 375hp nitrous kit. The Cruze to that car was a moped to the Starship Enterprise. I didn't get this car for the torque.

I realize it needs to be wound up, but I shouldn't have to drive around with the clutch halfway in and think I'm driving a 2 stroke 125cc dirtbike. If you take off in first and floor it, any car should accelerate. Mine at times will barely accelerate in first. When it does that, you can clutch it and put the gas on the floor and it literally takes seconds to rev up to 4000 rpm.

I filled up with 91 octane, which seemed to help in the rediculous heat we are having and welded in a Magnaflow muffler. It seems to be better now. Time will tell.

You're complaining about a lack of power and how slow the car is yet you claim you rarely rev the motor passed 2000 rpm? This isn't a big block that makes gobs of off idle torque, you've got to rev the motor up into its usable power band. Your motor is plenty capable of producing enough power to roll smoke off the tires all through 1st gear, you shouldn't have to worry about moving out into traffic...

I'm sure the hot summer weather has made the car feel a little slower than it did in early spring but you still need to wind the motor out if you expect the car to move.
 

·
Registered
Joined
·
58 Posts
You're complaining about a lack of power and how slow the car is yet you claim you rarely rev the motor passed 2000 rpm? This isn't a big block that makes gobs of off idle torque, you've got to rev the motor up into its usable power band. Your motor is plenty capable of producing enough power to roll smoke off the tires all through 1st gear, you shouldn't have to worry about moving out into traffic...

I'm sure the hot summer weather has made the car feel a little slower than it did in early spring but you still need to wind the motor out if you expect the car to move.
The 1.4 Turbo has all the torque it is going to get at 1850 rpms.

It is not a matter of heat or gas or or or... It is a small 4 cyclinder engine designed for fule sipping not high performance.
 

·
Premium Member
Joined
·
1,142 Posts
The 1.4 Turbo has all the torque it is going to get at 1850 rpms.

It is not a matter of heat or gas or or or... It is a small 4 cyclinder engine designed for fule sipping not high performance.
Torque is only a measurement of turning force, horsepower is what provides acceleration. At 1850 rpm the 1.4 is only producing 52 bhp, its peak of 138 bhp doesn't come until about 5000 rpm...
 

·
Registered
Joined
·
58 Posts
You're complaining about a lack of power and how slow the car is yet you claim you rarely rev the motor passed 2000 rpm? This isn't a big block that makes gobs of off idle torque, you've got to rev the motor up into its usable power band. Your motor is plenty capable of producing enough power to roll smoke off the tires all through 1st gear, you shouldn't have to worry about moving out into traffic...

I'm sure the hot summer weather has made the car feel a little slower than it did in early spring but you still need to wind the motor out if you expect the car to move.
Torque is only a measurement of turning force, horsepower is what provides acceleration. At 1850 rpm the 1.4 is only producing 52 bhp, its peak of 138 bhp doesn't come until about 5000 rpm...
Was just point out your post. I know all about HP and TQ.
 

·
Super Moderator
Joined
·
5,229 Posts
I have the 1.8 with MT and mine is a dog off the line also. It does not seem to have much power below a certain RPM range(1500 PRMs) I have driven a stick for many years and always push the clutch in before stopping. I noticed that the engine stalls when I do this and wait to long. It does not want to come back after @600 RPMs and just stalls. My previous cars also had a 2.2 or a V6 maybe that is what is causing the stalling issues. Anyone else experience this? I was considering the dealer for the doggy ness of the line tho. Im sure they will say it is OK tho since they cannot put a code on it.
 
21 - 40 of 63 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top