Charger Forums banner
1 - 20 of 31 Posts

·
Registered
Joined
·
575 Posts
Discussion Starter · #1 ·
All:

I am having a problme with my RT when I have been running the engine for a while and I stop for a short time. When I get back in the car, it cranks strong, but it sometimes takes 10-15 seconds of cranking to get it to fire up.

When the engine is cold or has been sitting for more than a couple of hours, this never happens.

My engine has 5800 miles and I have noticed this issue since about 400 miles when I put in my K&N CAI. I have done computer resets, tried all the Flashpaq modes, returned it to a stock program and still have the problem. Could this type of problem be related to the air intake senso that you move from the factory AI to the aftermarket CAI? I know it was a PITA to get that thing out of the factory tube.

Does that Sensor do anything to change the aire/fuel ratios and could this cause a delayed start? If that sensor goes bad, should it throw a code or does it only throw codes when it is functioning?

Thanks in advance as this is driving me crazy and I ahve been to the dealer three times, been unable to make the issue happen in front of them and of course they say no codes, nothing wrong.
 

·
Registered
Joined
·
2,069 Posts
I have been to the dealer three times, been unable to make the issue happen in front of them and of course they say no codes, nothing wrong.
OK, how can you not make this happen at the dealer, if it happens all the time with you. I'm sure you have a pretty good idea on how long to wait until you attempt to start the car again.

Try once again, this time just hang out at the dealer for however long it takes to "re-start" the car.
 

·
Registered
Joined
·
575 Posts
Discussion Starter · #4 ·
Okkay Crow, thanks for the obvious suggestion of hanging out at the dealer which is what was required to show this problem and the exact reason why I wrote the post in the first place. I could not demonstrate the issue without investing a significant portion of the day at the dealer. So I took a vacation day from work on monday and parked myself at the dealer. Within an hour and 15 minutes I made the issue happen for the tech. But then they said oh just wait around as I am sure this is soemthing we can fix quickly with the computer scan.

Well two and half hours later I went out to the bay and the guy looked at me like he had no idea what to say and then he said I have no idea what to tell you. He had been on the phone with STAR and they had nothing. So I left the car with them until late today and they upgraded the PCM code, cleaned the injectors and still had nothing. Problem occured one hour after turning the car off after leaving the dealer and has happended twice since then.

By the way, the tech asked me before I left what type of gas I put in it and I told him never anything but premium since the first tank. His response was to tell me to try using cheaper gas that maybe the higher octane was causing the issue.

How crazy is that response? 6000 miles on her and still no answers.
 

·
Registered
Joined
·
428 Posts
Get the same problem from time to time. Drive home from work, then car sits about an hour, when I go back out it sometimes doesn't start on the first try. 2nd try it always works.

What I've noticed is in the morning I may turn the key for 3-5 seconds until it kicks in. When its warm, I may only crank it 1-3 seconds because it sounds like its kicking in quicker and I stop turning the key to early.
 

·
Premium Member
Joined
·
5,973 Posts
By the way, the tech asked me before I left what type of gas I put in it and I told him never anything but premium since the first tank. His response was to tell me to try using cheaper gas that maybe the higher octane was causing the issue.

QUOTE]

your not supposed to use premiun in the r/t's the tech at the dealer said not to use anything but plus he said premium can foul the plugs
 

·
Registered
Joined
·
575 Posts
Discussion Starter · #7 ·
That is the first I ahve heard of that. I have read a heck of a lot of posts on here and never heard anyone say that about the premium gas. Has anyone else heard this recommendation before?
 

·
Registered
Joined
·
471 Posts
Are you using the same gas station? I used to have problems with gas from a particular Shell station in a modded Dakota I had. Problem went away with use of a different brand of gas. Could be your car is just sensitive to a particular brand, or that your gas station is selling sub par gasoline.
 

·
Registered
Joined
·
191 Posts
One possibility is the problem is temperature dependent (hot engine). If no sensors are bad, low fuel pressure could be causing vapor lock.

Back in the day, hot start problems were usually a bad coil or bad fuel pump.
 

·
Registered
Joined
·
2,069 Posts
A wasted day at the dealer.....that sucks, but at least you now have documentation of this issue and finally verified by the dealer.

Run one tank of 89 from a reputable gas station and see what happens. Who knows, it could be related to the gas.

Keep us posted on your results.......
 

·
Registered
Joined
·
191 Posts
From the Haynes LX service manual: Engine hard to start when hot:
1. Air filter dirty.
2. Fuel not reaching fuel injection; check for vapor lock brought on by clogged fuel tank vent lines.
3. Bad engine ground connection
4. Fuel injection or engine control systems malfunction.

#4 obviously isn't much help. But did remind me of a ShelbyZ I had that had a leaking fuel injector. Car would start fine when cold or after sitting for more than an hour; had to crank it a while to start after shutting it down for just a few minutes. Diagnosed by removing spark plugs and looking into the cylinders; the cylinder with the leaking injector had a wet piston.
 

·
Registered
Joined
·
575 Posts
Discussion Starter · #13 ·
I am planning on running this tank of gas down and then running 89 for several tanks. I have been using primarily Shell 93 Octane with an occasional other brand here and there. The Air Filter Dirty makes me wonder about the link of this problem to the time I installed the K&N CAI. THis is really the point where I noticed the problem starting but then again I put it on before I had 1500 miles on the car. I know the K&N Filter was new, but could I ahve fouled up domething in the install? Not sure what I might have fouled up on something so straightforward. But if the gas doesn't change anything, I think I will take off the CAI and put back on the factory airbox and try that.
 

·
Registered
Joined
·
575 Posts
Discussion Starter · #14 ·
1 question for xring:

Does that manual tell you how to check for a bad engine ground connection?
 

·
Registered
Joined
·
191 Posts
I don't have it with me right now but I'll have to look later.

Usually there is a bare metal woven wire strap somewhere connecting the engine with the body.
 

·
Registered
Joined
·
575 Posts
Discussion Starter · #16 ·
Well I have now run through a full tank of 89 Octane from Speedway and the engine has cranked beautifully everytime I ahve stopped the engine for around an hour. It hasn't been long enough to know for sure if this is the solution, but it is looking good. I am baffled. What about higher octane gas could be casuing this problem? I know there is an expert on here that will help me understand this better, but if I can't run a high octane gas, what good is the SuperChips 91 Octane tune?
 

·
Premium Member
Joined
·
5,973 Posts
Well I have now run through a full tank of 89 Octane from Speedway and the engine has cranked beautifully everytime I ahve stopped the engine for around an hour. It hasn't been long enough to know for sure if this is the solution, but it is looking good. I am baffled. What about higher octane gas could be casuing this problem? I know there is an expert on here that will help me understand this better, but if I can't run a high octane gas, what good is the SuperChips 91 Octane tune?
i have alwase been told that certain cars should run certain gas. our chargers= plus maybe cus they went toward sedan market?
high end lux cars like bmw=premium lux car lux gas?
trucks=reg its a truck beat the hell outta it?

if sum1 knows forsure i would love to kno real reasons as well
 

·
Registered
Joined
·
12 Posts
I have run nothing but 89.5 in my 2006 5.7 Daytona. And have no problems at all. In the manual on page 237 it reads "The manufacture recomends the use of 89 octane for optimum performance. The use of premium gasoline is not recomended" thats for the 3.5 and 5.7L engines. It also states not to use any gasoline containing Methanol.
 

·
Registered
Joined
·
70 Posts
Well your prayers have been answered. Had the same exact problem with my 06 R/T. It started around 5K miles and continued until they finally figured it out almost 25K miles later. First off we logged evertime it would happen. In the morning, evening, cold, warm, day, night, and the milage at which it happened. It would some times do it 3-4 times in one day.
Again, the same problem you had, "Tech can't get it to do it". So we went on vacation for a week and left it at the dealer for the tech to drive every day. After we got back they had a list of nemerous times it had done it. Then they had to take it up the chian to get approval to work on it since we were supposedly the first one's with this problem.
Come to find out it was the crank trigger ignition sensor. Small cheap part that since fixed, 10K miles ago, has not had a problem starting.
It was a real pain with my auto start. It would crank 2-3 times before actually starting up. By that time I was at my car sitting in the seat ready to go.

Crank Trigger Ignition Sensor
Take that to your dealership, if they've gat a problem let me know and I'll have my guy at the shop give them a call.
 

·
Registered
Joined
·
2,069 Posts
i have alwase been told that certain cars should run certain gas. our chargers= plus maybe cus they went toward sedan market?
high end lux cars like bmw=premium lux car lux gas?
trucks=reg its a truck beat the hell outta it?

if sum1 knows forsure i would love to kno real reasons as well
It is based off the cylinder compression of the engine. The higher the compression, the higher the octane is required. The 5.7 Hemi is a high compression engine.

Basically, the air/fuel mixture will "explode" under pressure without a spark. When this happens, you have detonation or knock. Ideally, you want the point of detonation just after the point of spark.
 
1 - 20 of 31 Posts
Top