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Post by mylexus420 on Jun 2, 2010 14:34:52 GMT -6
My car will hesitate when it is cold. Once it gets up to about 150-160 degrees it runs fine. What I mean is that when I first start my car and try to take off, it just doesnt want to go. It doesnt make any wierd noises at all, no back fire, its just like I'm not givin it gas. Also every once in a while when I get to wherever I'm goin and put it in park the idle will be around 1000 RPMs. Normally it is around 600. I don't know if the two are because of the same problem or not. Any help that someone can give me will be much appreciated
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Post by RCSRGREAT on Jun 2, 2010 16:08:04 GMT -6
Well, first off - how old are the spark blugs? Maybe thats why its idling high. Second, my car does this sometimes, if we are talking about the same thing. My car will be in the drive way or anywhere really and when i start the car and give it gas its like it is in neutral or something for about 3-5 seconds and then slowly pops into gear and goes. Mine isnt every start up though, its here and there- if its been sitting for a long time without moving/over night some times, even then it doesnt do it every time. Is this happening on every start up for you? ive been told many things by many people that it could be a solenoid or a clutch plate and even that my tranny is going out. Its been doing this for over a year. Ive tried taking it to a transmission shop even to have someone look at it and they told me everything looks good and they could only tell me what it is if it were to happen when they were there to see it and it wouldnt do it.. Just letting you know my experience.
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Post by mylexus420 on Jun 2, 2010 17:15:36 GMT -6
I replaced the spark plugs about two weeks ago with platinum plugs. When I give it gas it doesnt rev up or have any trouble gettin in gear. Ok, so when it is cold and I back out of my drive it is fine, I than put it in drive, and it shifts fine. I will be at a slow roll and than give it gas to build up speed and it seems like it just bogs out or somethin. It does not stall, its just as if I am not even pressin the gas. It does eventually get up to speed, but with a hesitation. Like I said it does not rev up like my transmission is not engagin, nor does it make any kind of noise that is not natural. This happens to me every time I take off and the car is not warmed up. I am wonderin if it is a sensor? Other than that a couple of things that I did prior to this happenin is I ran a can of seafoam throgh the tank with the tank full of gas. Also I recently took my mufflers off and put straight pipes on in place of them. Is there not enough backpressure maybe since the mufflers are gone?
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Post by RCSRGREAT on Jun 2, 2010 17:49:10 GMT -6
hmm.. idk, Ive never messed with my mufflers.. maybe Rob or Collins will look in on this thread- they have straight pipes as well. Maybe there could be a sensor problem, they may know. The only other thing I could think of is something to do with fuel pressure but you said it doesnt stall so im not sure.
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Post by mylexus420 on Jun 4, 2010 5:45:19 GMT -6
Well thanks for the input, we'll see if anybody else has any ideas. If not than I will just have to take it to Tuffy's to have it diagnosed. I will keep the thread posted just in case anyone else has this problem.
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Post by 55624096 on Jun 4, 2010 6:39:26 GMT -6
Have encountered this cold "bog" and have determined it is not the spark plugs or fuel pressure but the wires. I think that when the wires get old they leak from the rubber insolator that covers the spark plug and when the engine is cold ( time of great resistance) the spark jumps and shorts out the spark. When engine gets hot the resistance to firing goes down and you have no problem. It is probably only one or two wires but it is very difficult to find which ones. Usually it is the ones closest to the firewall, 1,3,5,7. Would like to have feed back to determine if this is your fix.
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Post by auroraphoenix on Jun 7, 2010 1:39:42 GMT -6
Posted by 55624096 on Jun 4, 2010, 7:39am Have encountered this cold "bog" and have determined it is not the spark plugs or fuel pressure but the wires. I think that when the wires get old they leak from the rubber insolator that covers the spark plug and when the engine is cold ( time of great resistance) the spark jumps and shorts out the spark. When engine gets hot the resistance to firing goes down and you have no problem. It is probably only one or two wires but it is very difficult to find which ones. Usually it is the ones closest to the firewall, 1,3,5,7. Would like to have feed back to determine if this is your fix.
You say resistance goes down as the engine gets hot? I thought it was the opposite?
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RCA1186
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Post by RCA1186 on Jun 7, 2010 13:13:15 GMT -6
I really don't think that removing the mufflers on these cars causes much, if any, backpressure change. If you cut the muffler off and look inside you will see that its pretty much just a pipe straight through without any visible baffles or anything, plus I never noticed a ticking or change in rpm's etc after removing mine.
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Post by mylexus420 on Sept 29, 2010 9:38:11 GMT -6
Update:
Finally got around to replacin the wires but still have the same problem. Its definitly not the transmission but is somethin with the engine. Any other ideas would be greatly appreciated
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Post by lanceslambos on Sept 29, 2010 9:53:19 GMT -6
i wonder if your throttle linkage is just sticking & your not really noticing. it can be a common classic problem but only needs fixed/ cleaned and lubed once & your good.
if the car is changing idle between 600 & 1000 rpm then it's still warming up & u should just let it do it's thing for 20-30 seconds. possible suspects: tranny solenoid? or maybe the butterfly is sticking or hanging in the TB if a plug or wire isn't your problem, i'd venture looking into the TB and get it cleaned. seafoam may not be enough. but this could even be a simple spark plug or even dirty ground somewhere. i don't think it's too much to worry about yet.
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XJSman89
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Post by XJSman89 on Sept 30, 2010 9:02:55 GMT -6
I was going to suggest wires. I had a similar problem and new plugs and wires fixed it. here's something you can try:
My engine only bogged down while under load. The next time it hesitates stick it in neutral and run it slowly up to redline and see if it still hesitates. If it does then that will rule out the trans as a contributing factor.
I've never had a problem with my straights and backpressure and I've had my pipes for almost two years now.
This is confusing... Maybe your FPR is going out?
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scottydl
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Post by scottydl on Sept 30, 2010 10:29:16 GMT -6
Sounds weird, but check your battery connections (under the back seat). Some time back, I had a bunch of chalky corrosion on my battery terminals and somehow must have gotten in between the metal connections and interrupted the electrical signal. It wreaked havoc with the car computer or sensors somewhere, and I could floor the pedal and the car would barely sputter along. Once I cleaned up the battery, no more problems.
Ignition coils (where your spark plug wires attach) are also the next thing to check in line with spark plugs and wires. There are 4 of them, each with 2 wires running to it. Use a multimeter to measure the resistance/ohms between each post, and you should get somewhere around 6500 on the meter. A bad coil could cause an erratic electrical signal and cause problems.
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Post by ntrenn on Sept 30, 2010 12:48:44 GMT -6
Have you checked fuel pressure?
When cold, the engine needs much more fuel than it does when warm, and if your fuel pump is low on delivery volume, you'll get cold driveability problems. My old beater truck was horrible for about a year before the fuel pump finally couldn't send enough fuel to keep it running. New pump, all the cold driveability problems went away.
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Post by Deleted on Oct 1, 2010 6:58:33 GMT -6
I agree with scotty on this one. I had a cold stumble, it would recover only when throttle was 3/4 of the way down, and in the winter with ice covered roads...that is not fun. I suggest checking your coils and replacing if needed.
Posting the year and mileage of your vehicle can say alot too. Say your car has 200k miles. It could probably use new coils anyways. They are an easy do it yourself thing to.
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bobsblue95
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Post by bobsblue95 on Oct 1, 2010 14:48:18 GMT -6
Have you done any mods to the car? like a cold air intake?
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Post by mylexus420 on Oct 2, 2010 1:03:25 GMT -6
It is a 96 with 146k, and no I do not have a cold air intake. I did gut my airbox however and take the resonator off. I will test the coils tomorrow and see what I get. It is a little late now seein as it is 3 in the mornin. Im on a third shift schedule and didnt have to work tonight.
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Post by mylexus420 on Oct 7, 2010 10:48:16 GMT -6
OK, I'm getting readings of between 5500 - 5600 ohms, so they for sure need changed right. Also would that difference, or wear, in the coils cause the problem I am having. And back to the high idle, it isn't only on cold starts. The engine can be at running temperature and when I come to a stop it will have a high idle, and within the last couple days the idle has gone up another 100 revolutions.
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Post by ntrenn on Oct 7, 2010 12:36:48 GMT -6
Fuel, fuel, fuel....do you have enough fuel? Key indicator is fuel pressure. You classic guys should have 45 psi or more fuel pressure at idle.
Coil resistance is only good indicator of coil performance if they are open. Coils also tend to go bad as they warm up, not get better....
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scottydl
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Post by scottydl on Oct 7, 2010 19:20:50 GMT -6
OK, I'm getting readings of between 5500 - 5600 ohms, so they for sure need changed right. Not necessarily... really the more important indicator is if 1 of the 4 coils is giving a reading substantially different than the others. Then THAT one would likely be faulty. It's pretty unlikely coils would all go bad at the same time, requiring you to replace them all. Fuel pressure should be the next thing to have checked. Any shop should be able to do that pretty easily, without charging you an arm & leg.
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Post by clutch1 on Oct 7, 2010 21:02:27 GMT -6
Don't forget fuel volume!!!!!
While it's running press the purge button on the gauge and let it go for 15 seconds. Should get 15oz of fuel purged!
Pumps lose volume before pressure, generally!
As for high idle, make sure your idle stepper motor and throttle body is clean, not gunked up, no carbon on the manifold side, etc.. For starters at least.
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