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Discussion Starter #1
I have a 92 Dodge Dynasty with a 3.3L V6 that every once and a while (usually when the weather gets warmer) it seems that the engine starts to idle kind of rough and then while I go to accelerate from either a red light, go up a hill or merge onto a highway the speedometer will start to drop and the engine starts sputtering and I can press the pedal down to the floor with no response from the engine. The first time it did it was starting out from a red light on about a 100 degree day. Second time was merging onto a highway (about 50 or so degrees) the second I hit 55. Check engine light does not come on and it usually fixes its self after pulling over and restarting the engine. I have all ready had the spark plugs and wires replaced. Any ideas what it could be?
 

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Did you have this before the plugs and wires? Are the new plug tips carboned up black?
Pull the vacuum hose off the fuel pressure regulator and check for raw fuel.
Road test with a fuel pressure gauge?
 

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Discussion Starter #4
I checked the engine codes as best I could with what I had right after it happened (did the key on off thing and all I got was code 55). I appreciate the other suggestions but as of writing this frist post my car is out of commission for the time being (or permanently depending on what I can afford). On my way to work my transmission started acting up, car started lurching forward and shaking violently as it was trying to shift and after finding an opening and getting into a neighborhood I discovered that I no longer had a reverse gear. Could floor it in reverse all day long without moving. So after pushing it out of a driveway by my self I ended up getting it towed to the transmission shop that a few weeks earlier told me that had just replaced the fluid and filter about 2000 miles ago (which now smells like burned rubber) and told me that I just needed some cooler lines and a axle seal replaced because they had a TINY leak and I quote from the technician "if it were my car I would have NO problem driving it to California after replacing the lines and seals" After I have a nice little discussion with this guy about this I will NEVER go back there (may take it up with their corporate office as well since he pretty much cost me a transmission)
 

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Sorry about the reverse failure. Keep your eyes and ears open for a good used A-604 (41TE) transaxle, pre-1996.
If it is the original transaxle, there have been so many upgrades added since 1992 that many shops won't even try to rebuild them and suggest a reman with the upgrades already done.
The key-dance is only good for getting engine (PCM) fault codes and not everything leaves behind a code. The transaxle (TCM) module may have other codes that would need a special cable and scan tool to read.
 

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Here are my thoughts on the transmission:
If it is just the axle seal and line, then you should be able to refill the transmission and it would drive fine until it leaked out enough fluid again. If that does not work then it needs more repairs.
If it's leaking that bad, I don't see why they did not mention it when they serviced it before.
I really have to wonder what fluid they used (ATF+4 is good, Dexron even with the additive is bad).
As for the engine:
Besides fuel, it could be the crank position sensor. They won't always leave a code behind.
 

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I had the shudder shift and slipping gears with no downshift / little reverse on my 89 New Yorker - turned out to be the throttle position sensor which didn't throw a code. Let's not forget the A604 has no valve body and is controlled purely by a solenoid pack driven by the TCM. The falling speedometer and loss of power also look electrical. SOmetimes we get so wrapped up trying to diagnose problems in complicated machines we forget the basics. How is the ground from the engine to body? How good are the positive battery wires connected - there's more than a couple on mopar so just because it cranks good doesn't mean the one for the body/ecm is that great. Do a wiggle test on the harness and various connectors while it's running and see if it stalls - don't forget to smack the column on the bottom and wiggle the key to check the ignition switch.

Hop this helps - Good luck!!
 

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Discussion Starter #8
Got the transmission replaced. The shop did not say exactly what had broken (it was something inside) but they said the fluid was almost black and the thing was shot. Had a professionally rebuilt transmission installed and it is running great.

I'm going to be replacing the valve cover gaskets and the air plenum gasket due to the gaskets being pretty much gone causing a large oil leak (auto parts store said I had to replace the plenum gasket since it has to come off to access the rear valve cover) as soon as it warms up enough not to freeze while working on it (I don't have a heated garage). One question I have is do I or do I not need gasket sealer on the gaskets and if so what kind do I need? I keep finding tons of different information all over the internet and I am not sure which to trust. The plenum gasket is a sort of cardboard or something like that (plus about 4 other gaskets that I'm not sure what they go to that came in the box) and the valve cover gasket is some sort of thick blue rubber. Sorry about the stupid question but I just want to make sure I do this right
 

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You should not need any sealer. The FelPro blue valve cover gaskets are very good, I am assuming that's what you got since they are blue. I suspect the other gaskets with the plenum gasket may be for the throttle body and the like.
 

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Discussion Starter #10
valiant67 said:
You should not need any sealer. The FelPro blue valve cover gaskets are very good, I am assuming that's what you got since they are blue. I suspect the other gaskets with the plenum gasket may be for the throttle body and the like.
Yep they are the FelPro valve cover gaskets. I've been told that they were the better choice of the two that the autopart store had. I think one of the gaskets is the throttle body and the other two I'm not sure. They are pretty small maybe some kind of sensor or a small pipe?
 

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Could be part of the throttle body. I've never had a chance to take apart a 3.3 TB, but the 2.5 TBI throttle body splits in half, with a gasket between the two halves. If you haven't removed a gasket that resembles the ones in question or found evidence of a gasket on the disassembled parts, I wouldn't worry about it. My general rule is "if it didn't have a gasket from the factory, it doesn't need one now". What I've found is that gasket kits often cover several different applications and include gaskets that aren't necessary on some applications so that the manufacturer can make one kit and sell it for a bunch of applications.
 

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You mention plugs and wires but have you ever had your coil pack checked, all you need is a dvom and a repair manual for specs chances are it could be going bad and changes in the weather like a hot day or humid or anything could cause intermitent problems like what you are experiencing, fuel problems like the fuel pump, you have fuel flow and volume, volume is like when you first go to start the car and it cranks and no fire, then you stop cranking and hit the key again and it fires up, that usually indicates your fuel pump can not supply the fuel needed for startup like it is supposed to, usually a bad pump usually just quits altogether, in rare cases will it ever sputter like that. usually the car will buck and shake and backfire for lack of fuel and good spark, fuel injectors usually don't go bad unless you own a GM, then you check those as well.

Ohm out the coil pack and go from there, and the first obd I systems don't pick up misfires like obd II and chrysler computers are way advanced compared to ford and gm and compensate a lot for misfires and make them hard to detect. almost makes the car smooth running when it shouldn't be.
 

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In addition to what raymondo said, check the coil pack for green corrosion on the connectors. I had that happen once and just about drove me crazy before I found it.
 

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Discussion Starter #14
I checked the coil pack today and although I could not figure out which set of values I should have been reading (the haynes book has a listing of values for Diamond, Toyodenso and Marshal which I'm assuming are brands but I could not find any information on mine besides a part number and Made in Japan) the numbers were pretty close to what was in the book. For the connector with the 4 pins I got around .7-.8 ohms for those and for the ohm readings between the terminals that the spark plug wires connect to I got about 12.6-13 k-ohms.

Could not check my spark plugs because turns out the sparkplug socket that I have is not the right size so I have to go to the store and buy a larger one. Also looked up the crankshaft position sensor in the book and it says I can't diagnose that without some kind of computer stuff so I did not mess with that. It told how to replace it but said I need a shop to tell me if it's good or not.

Also can a dirty throttle body cause an engine to act up like this? Looked at mine today and it needs to be cleaned. Also how exaclty do I clean it?
 

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You can and should also check the coil pack after its ran and gets hot, and see what happens that's probably when you will have the problem with it, when the pack gets cool again things go back to normal making it hard to diagnose, remember the problem happens when the car has been running and after everything is good and hot, that is what we call simulation and that's how you can be more accurate in diagnosis, no a carboned Throttle body will not cause those problems, the problems associated with those when they get carboned is after you disconnect the battery and go to turn the car on it can suddenly die and not want to run at idle but under acceleration it is fine, this happens to a lot of vehicles when you change the battery and erase the cars memory in the computer usually on cars with over 60K miles or higher, it can not find the right spot for the AIS motor to reach to keep it running at idle because it goes back to factory settings, which is why it is good to clean the TB when you change the battery on any car to avoid this, use a good Throttle body cleaner I like 3M and use a rag and wipe it out, and make sure you clean the butterfly you don't need to saturate it that is unneccessary just use enough to clean it, and do not by any means use carb cleaner it is not the same and should be avoided.

Also what plugs are you running there? you should be using champion the copper ones are fine chrysler motors are designed for champion plugs only and a different plug has a different wear rate, in that porcelin insulation there is a resistor and different brand plugs have different size resistors in them, 3.3's normally are not fussy like the 3.5's those act like a real bear on a different plug after a while I seen people get close to junking cars with those motors due to bad plugs or using anything but a champion, and when you tell them its the plug they are like no way I just changed those not too long ago and thats when I tell them and they go I heard champion plugs are garbage and I tell them don't believe everything you hear use factory OE parts to avoid problems that's why it is put on a tag under your hood with the proper gapping. Also a bad plug will cause a misfire that you will notice at idle and more on acceleration and you can detect on a scanner or a live data code reader by simply changing the plug in the misfiring cylinder to another cylinder and you will see the miss change to that cylinder its real cool. So I doubt you have bad plugs, I am still banking on your coil pack, they are not expensive to replace either, 35 dollars us is the most I have paid, denso packs were made in japan bet that's what you got, coincedentally Toyota uses the same brand even the starters and you can fix a denso starter for 5 to 10 dollars on that car too. I love having Chryslers don't know why America still prefers GM garbage. I sure love the money they pay to work on them though. L.O.L. Also another thing that makes cars act like that under acceleration is the oxygen sensor but that usually throws a code as well, but this is another thing your ecm relys on for air fuel ratio, remember oxygen sensors only detect oxygen they are not fuel sensors, so the ecm regulates the amount of fuel based on the amount of oxygen in the mix, if the sensor which is a galvanic battery and changes voltage based on engine temp to indicate mixture, to test this you will have to use a T-Pin and go into the the connector with the pin find the pos. output put your volt meter to dc and warm the engine to normal temp run it at 2000 rpm for a short while, now ground your meter and hit the T-pin a good o2 sensor can switch rapidly and should fluctuate and change voltage as the engine warms, you can do a before the engine warms test and after to see the difference. If it is slow to change, change it out or if it does not change at all in volts change it out.

Checking the fuel PSI on the rail isn't bad either, you can rent most of the tools from crapzone or autozone, they are not bad in that aspect. How is your fuel economy on the car is it bad or good, has it went down, increased, changes in fuel economy can help pinpoint problem areas as well.

Anyone can change parts on a car, but to be able to diagnose and know how is what makes you an auto technician.
 

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Discussion Starter #16
raymondo112 said:
You can and should also check the coil pack after its ran and gets hot, and see what happens that's probably when you will have the problem with it, when the pack gets cool again things go back to normal making it hard to diagnose, remember the problem happens when the car has been running and after everything is good and hot, that is what we call simulation and that's how you can be more accurate in diagnosis, no a carboned Throttle body will not cause those problems, the problems associated with those when they get carboned is after you disconnect the battery and go to turn the car on it can suddenly die and not want to run at idle but under acceleration it is fine, this happens to a lot of vehicles when you change the battery and erase the cars memory in the computer usually on cars with over 60K miles or higher, it can not find the right spot for the AIS motor to reach to keep it running at idle because it goes back to factory settings, which is why it is good to clean the TB when you change the battery on any car to avoid this, use a good Throttle body cleaner I like 3M and use a rag and wipe it out, and make sure you clean the butterfly you don't need to saturate it that is unneccessary just use enough to clean it, and do not by any means use carb cleaner it is not the same and should be avoided.

Also what plugs are you running there? you should be using champion the copper ones are fine chrysler motors are designed for champion plugs only and a different plug has a different wear rate, in that porcelin insulation there is a resistor and different brand plugs have different size resistors in them, 3.3's normally are not fussy like the 3.5's those act like a real bear on a different plug after a while I seen people get close to junking cars with those motors due to bad plugs or using anything but a champion, and when you tell them its the plug they are like no way I just changed those not too long ago and thats when I tell them and they go I heard champion plugs are garbage and I tell them don't believe everything you hear use factory OE parts to avoid problems that's why it is put on a tag under your hood with the proper gapping. Also a bad plug will cause a misfire that you will notice at idle and more on acceleration and you can detect on a scanner or a live data code reader by simply changing the plug in the misfiring cylinder to another cylinder and you will see the miss change to that cylinder its real cool. So I doubt you have bad plugs, I am still banking on your coil pack, they are not expensive to replace either, 35 dollars us is the most I have paid, denso packs were made in japan bet that's what you got, coincedentally Toyota uses the same brand even the starters and you can fix a denso starter for 5 to 10 dollars on that car too. I love having Chryslers don't know why America still prefers GM garbage. I sure love the money they pay to work on them though. L.O.L. Also another thing that makes cars act like that under acceleration is the oxygen sensor but that usually throws a code as well, but this is another thing your ecm relys on for air fuel ratio, remember oxygen sensors only detect oxygen they are not fuel sensors, so the ecm regulates the amount of fuel based on the amount of oxygen in the mix, if the sensor which is a galvanic battery and changes voltage based on engine temp to indicate mixture, to test this you will have to use a T-Pin and go into the the connector with the pin find the pos. output put your volt meter to dc and warm the engine to normal temp run it at 2000 rpm for a short while, now ground your meter and hit the T-pin a good o2 sensor can switch rapidly and should fluctuate and change voltage as the engine warms, you can do a before the engine warms test and after to see the difference. If it is slow to change, change it out or if it does not change at all in volts change it out.

Checking the fuel PSI on the rail isn't bad either, you can rent most of the tools from crapzone or autozone, they are not bad in that aspect. How is your fuel economy on the car is it bad or good, has it went down, increased, changes in fuel economy can help pinpoint problem areas as well.

Anyone can change parts on a car, but to be able to diagnose and know how is what makes you an auto technician.
I think the spark plugs are Autolite plugs but I need to go check. I'll drive the car around for a while tomorrow to get everything nice and warm and then check the ignition coil again. I never even thought about the temperature causing me to get a false reading.

I checked the websites for the auto parts stores around here and it looks like the coil pack for this car is anywhere from 60-105 dollars. Also are any brands better than others? I keep seeing BWD come up (except on napa's site but it's the same BWD part with Napa's name on it)


Well when I first got the car the gas mileage was terrible. I was getting around 17mpg at the time. Then once I had the plugs and wires replaced it went up to about 19 mpg.
 

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Mileage will be helped by a throttle body cleaning. It may not solve your problem specifically, but it's a good thing to do if you think it needs it. I would go with pretty much any coil pack, unless the price is ridiculously low. Coils are pretty robust by nature. I wouldn't spend extra money for "high performance" coils; it's pretty much agreed upon that the Chrysler stock coils (at least on the 2.2/2.5, but I imagine on the 3.3 as well) are plenty powerful enough.
 

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Discussion Starter #18
Pulled out one of the spark plugs today to see what they looked like. I noticed that there is a lot of oil from the valve cover gasket leak that pooled up around the spark plugs and when I pulled the plug out there was a coating of oil on the threads. No oil on the tip of the plug just the threads. Here is a picture

 

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Discussion Starter #19
Did another test after the engine was warmed up. Accross the spark plug terminals I got about 14 ohms and for the pins in the connector I got .5-.7 kilo ohms. They were different than the cold test but I think they seem ok. What do you guys think?
 

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I don't know about the resistance values specifically, but the plug looks pretty good to me.
 
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