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spoolin_gt
02-24-2005, 12:11 AM
ok...so i've been having this problem with my car...i wont boost at all when the car is not at normal temperatures..i have to let the car idle for atleast 15 mins or so before i can drive it or else people will start honking at me because car won't really accelerate...car will move fine when the vac is between 20 and before 0...once it reaches boost..car won't accelerate...and the only time the car runs fine..is when it's at normal temp...anyone else experience this problem???

carlosfandango
02-24-2005, 02:08 AM
never boost a cold engine, your asking for trouble, once everything is lubed at norm operating temp then its safe to boost - when you get up out of your bed your not fit for a sprint til you are awake and alert. a car is no different and needs to stretch its legs.

imho you only boost when cold off the green light for a drag run which should only be done often if your engine can take it.

sounds like you have a auto choke problem or cam timing.

Lagos
02-24-2005, 02:15 AM
it seems to be a common problem with the 3sgte.

by "boosting" i dont think he means WOT, 13psi. its more of a problem with daily driving and hiting 1-5psi.

Snafu
02-24-2005, 02:15 AM
Has this all started recently? Has it always done it?

To me it sounds like (and forgive my lack of 3sgte lingo) the TVSV is telling the ecu that your engine is cold, and so your ecu is retarding timing. Now, please PLEASE correct me if I'm wrong on that, haven't owned a 3sgte, so I don't know for sure.

spoolin_gt
02-24-2005, 04:09 AM
i dont mean wot...i mean..just boosting in general..my car needs to boost..or any other 3sgte to pick up speed...i know better than not to slam on the pedal when the car is cold...

it never happened before when the weather was warmer....it just happened recently..bout a month or so ago...it's not the tvsv since it's disconnected...aniways..it runs fine once it's warm...but it's embarrasing to get honked at in the middle of the road..better yet the highway..when you're going 40 and everyone else is going 100....

Lagos
02-24-2005, 06:12 AM
i know exactly what you mean and have the same issue. it seems to be a mystery as to why this happens. tons of alltrac and mr2 guys report the same problem. some people said that changing the Coolant Temp Sensor helps.

galcrazi
02-24-2005, 11:22 AM
Has this all started recently? Has it always done it?

To me it sounds like (and forgive my lack of 3sgte lingo) the TVSV is telling the ecu that your engine is cold, and so your ecu is retarding timing. Now, please PLEASE correct me if I'm wrong on that, haven't owned a 3sgte, so I don't know for sure.

This is correct. And no you dont HAVE to boost at all to accelerate. The 3sgte pulls faster up to 0 (atmosphere) than a a 5sfe. Also, just a thought, alot of you who have done the swap did not swap in your gt4 radiator, therefore, your fan is constantly running. I have heard of some swappers having problems getting their cars up to normal op temps bc the fan is constantly running. Just a thought.

Lagos
02-24-2005, 01:21 PM
im on my 5sfe radiator and my fans work like normal.

Luni
02-24-2005, 03:25 PM
My car does it as well, however I know I have a broken sensor that has something to do with the cold start/just plain cold fuel delivery circuit.

You people with issues in the cold. Do your cars start right up or does it take a second of cranking to get them to fire?

spoolin_gt
02-24-2005, 10:05 PM
it starts up fine...no problem at all....

and yea..im using a 5sfe rad as well..but it's running ok..it's not going on constantly..

it's better asking people here...people at alltrac.net keep thinking that im driving the car "hard"..just cause im boosting....they don't get the fact that there's not way that i will reach 60km/h without boosting....i will reach that speed eventually but trucks, cars etc..maybe people running are taking over me and getting pissed off cause im causing traffic...

Lagos
02-25-2005, 12:51 AM
luni, at 1st my car would sometimes take a few cranks to start up on a cold day. it turned out the plug that goes to my cold start injector time switch was cracked and not making good contract with that sensor. i fixed the plug with crazy glue and now the car fires right up on the 1st crank.

Gary
02-25-2005, 04:28 AM
it starts up fine...no problem at all....

and yea..im using a 5sfe rad as well..but it's running ok..it's not going on constantly..

it's better asking people here...people at alltrac.net keep thinking that im driving the car "hard"..just cause im boosting....they don't get the fact that there's not way that i will reach 60km/h without boosting....i will reach that speed eventually but trucks, cars etc..maybe people running are taking over me and getting pissed off cause im causing traffic...

Not "people at alltrac.net keep thinking that im driving the car "hard"..just cause im boosting"
Just me! ;)
So what is the real answer to your problem?
And how do you solve it?

spoolin_gt
02-25-2005, 07:25 AM
hey Gary you're here too..;)..
ok...the fact is that it never happened before..it was pretty cold before..but it never happened before...try boosting your car..or just see if it your car will actually hit 1 psi...if it doesn't...then you're not having this problem...if it does....then..????...you're telling me that i'm driving it wrong because my car won't boost when it's cold????my buddies dsm will boost when it's cold...my other buddy's gt4 will boost when it's cold....some i know wit gt4 will not boost when it's cold....so this is defenitely a problem...so if you're gonna tell me again that this is not a problem..then you're really not helping at all....so when you experience this.....or will agree that this is a problem....you're more than welcome to post.....but if you're gonna keep telling me over and over again that im driving my car "hard" when cold because it will not boost....then you have yourself a good day....what i wanted to know is if anyone else is experiencing it and see if they did anything about it..to solve the problem not get people to tell me that im driving my car hard....that's it...

Gary
02-25-2005, 07:47 AM
Of course, I'm here too

http://img203.exs.cx/img203/8758/14ma.jpg

Seriously, I am trying to help you out.
According to you, your car acts normal when it's warm up.
My suggestion is, warm up the car before you get on the road. That the ultimate solution. Easy and simple.

BTW, I will not try what you suggest (hit the boost when my engine is cold)
I don't see a point of hurting my car just to prove this.
If you think it's OK to hit the boost when engine does not reach normal operating temp, do it.
It's your car. ;)

spoolin_gt
02-25-2005, 07:56 PM
Can you explain why it never happened before and it's doing it now???

Dragon008
02-25-2005, 10:45 PM
That same problem affects my all-trac. As soon as boost comes in it dies. It did take a long time to warm and yeah it did get bad when i had a bigass dodge coming too fast up my street, i tried to force it but it didnt like me for that and i limped over to the curb.
I hav replaced the temp sensor on the engine and intercooler, as well as watched engine temp, but nothing seems to help it excelpt a good warm up adn once at operating temp rev it to 2000rpm and thats it.
This problem started this winter, and i thought turbo or vacuum leak but nothing. I know im not supplying an answer with a solution, but i am saying that i have the exact same problem, and i live in scarborough, so we in the same climate.
Just another damn 'personality' of these engines. Ima go get me a civic!

enjoy

gt_turbo
02-26-2005, 12:49 AM
i dunno i hate the stock ecu... damn fuel cut... just get an ems guys. :D

spoolin_gt
02-26-2005, 02:35 AM
it has nothing to do with a fuel cut....

dragon..u live in scarborough??toronto??come out to the meet tomorrow at kennedy commons...starts at 8..

alltracman78
02-26-2005, 05:15 PM
To me it sounds like (and forgive my lack of 3sgte lingo) the TVSV is telling the ecu that your engine is cold, and so your ecu is retarding timing. Now, please PLEASE correct me if I'm wrong on that, haven't owned a 3sgte, so I don't know for sure.

This is correct. And no you dont HAVE to boost at all to accelerate. The 3sgte pulls faster up to 0 (atmosphere) than a a 5sfe. Also, just a thought, alot of you who have done the swap did not swap in your gt4 radiator, therefore, your fan is constantly running. I have heard of some swappers having problems getting their cars up to normal op temps bc the fan is constantly running. Just a thought.

It's not correct.
The TVSV has nothing to do with temp at all. The actual TVSV [I'm assuming you are confusing this with the MAP sensor] can only bleed pressure away from the wg actuator. The MAP sensor [turbocharging pressure sensor] only deals with fuel cut.

Even with engine timing retarded [unplugged knock sensor] you still have plenty of capability to accelerate, and boost.

Not swapping rad/fan has nothing to do with fan constant run.
Out of the rad/fan/fan temp switch, the only difference between the 2 [GTS/AT] is some small things on the rad.
In fact, I have a GTS rad/fan in my 92 AT right now.
The fan constantly running will only be caused by 4 things. The fan temp switch bad/unplugged, the ac high pressure switch bad/unplugged, the rad fan no 1 relay bad, or a problem in the wiring.

And the fan constantly running will barely increase warmup time. The coolant still isn't flowing, which is the real factor in this.

*What's up, Gary?! :hehe: *

alltracman78
02-26-2005, 05:24 PM
I'm assuming you don't have a cel?
Here's something you can try that [might] help you out.
Put a jumper in TE2 and E1.
The cel light should flash even.
Take the car on a drive, til it does the problem you are describing. Once it does this, go back, turn off the car, and put the jumper in TE1 and E1. This will possibly give you a code to work with.

spoolin_gt
02-26-2005, 05:39 PM
my main problem is that my cel doesn't go on...i have to try fixing that first...but thanks for the advice alltracman78...

alltracman78
02-26-2005, 05:49 PM
Ahhh

You defintely need to fix that. If the ecu is bad, that could definitly be causing your problem.

If you have a known problem, you need to fix it first, before trying to work on another one......... :squint:

Snafu
02-27-2005, 03:59 AM
Let me rephrase what I said. The coolant temp sensor is seeing that the car is cold, and the TVSV sees boost, so your ECU retards ignition timing. Correct?

alltracman78
02-27-2005, 04:21 AM
That makes a little more sense.
One thing, on the 3S, at least as far as this specific topic, it's the map sensor [or turbocharging pressure sensor], not the TVSV. T-VSV is turbocharging vaccum switching valve. It works in conjuction with the wg act.
Two, as far as I can tell, the general concencus [on the Alltrac/MR2 boards] is the only thing the ecu uses the map sensor for is fuel cut, tho you have a interesting point.
Three, even if the ecu is retarding timing, it won't create that drastic a power loss. Even with the knock sensor disconnected [automatically retards timing, you can still hit full boost [~10psi].
So even if the map works that way, it wouldn't cause this particular problem.

Snafu
02-27-2005, 02:57 PM
Well, I've just heard from a few 3sgte owners that the thing won't really boost when it's < 32 degrees outside. Does the 3sgte have an intake temp sensor, or just the coolant temp sensor?

alltracman78
02-27-2005, 04:23 PM
It has both.
Intake temp sensor is in the afm.
And it will defintely still boost below 32deg.
I had it at home in Jan when it was below freezing for almost the whole time. In fact, it hit below zero a couple of times. I couldn't give it full throttle 'cause it kept hitting 15psi.
I loved it tho. It felt like the car had a big V8 in it. It took almost no throttle to get going at a good speed.

Now if the car isn't warm, it's going to run like crap at that temp.

Luni
02-27-2005, 04:52 PM
My car does the same thing.. If IM partial throttle I can boost up to maybe 3 psi or so under load (definately my foot NOT in it) when its cold, but I have to wait till its all the way warmed up and then it takes off good.

Well.. Past tense. IT DID.. All up until it blew its engine.

Snafu
02-27-2005, 08:36 PM
I think he might have something more wrong then. 15 minutes is a LOT of time for a car to need to warm up. I let my car idle for 7 minutes in -20 weather and it's damn close to normal temperature. How's the thermostat?

Luni
02-27-2005, 09:39 PM
Yeah.. I dont let mine warm up idling. I drive it nicely until its normal then i boost.

It takes it about 5 minutes of driving to warm up.

DAMMMIT LET ME REPHRASE THAT.

IT DID WHEN IT RAN. ugh

alltracman78
02-27-2005, 10:35 PM
Well, he's definitly got something wrong....
He has no CEL. Maybe it's only the bulb, but it needs to get fixed before anything else is tried...

Snafu
02-27-2005, 11:09 PM
Well, he said it was fine from 20hg to 0, and from then on it was realy damn slow. I think it's that damn coolant temp sensor.