background: 90' RS 305 TBI, recently (about a month ago) did my intake manifold gasket, new pcv valve, did the plugs & wires a few months ago (correctly gapped), new fuel filter & fuel lines, new thermostat, new alternator, and others but i cant even think right now, so, after all these things, my car was running great, Now, when my car is accelerating or turning & accelerating, it kind of bucks a little & dosent have power at all, if i floor it, it takes a second, Then recognizes it. but still when its trying to GO its got like no power.. any suggestions?
ive tried: checking my IAC and adjusting my TPS didnt help. i checked my tranny fluid & it looks a little tan but still had a red tint to it & fluid is in operating range. can anyone help ? if you have questions that can help you diagnose feel free to ask

 

bttt

 

also forgot to mention i changed my oil right before i did my intake manifold gasket.

i took it on a ride today and realized my SES light dosent come on until my car is heated up. im still kinda stumped on this.. any suggestions?

 

Find out the code first. Are you low on gas?

 

nope, im at a solid quarter (well a little more than that, im rounding down) how do i go about pulling the codes? ive never done it & dont know how to read them either, all i know is the SES light will blink

 

I've got the same problem, only code I have is the MAF sensor. It's crazy though, my ses light only comes on a couple seconds after i let off the gas... push the pedal down and it goes away, let it off, comes back on. It's weird.

 

bttt anyone have any ideas?

 

i deleted my heater core hoses today and took it on a ride to make sure that it worked & isent leaking & my car is still having the same issuses but i noticed today that my ses light did not come on but my "shift" light stayed on the entire time. my car is an automatic but the cluster i put in it came out of a manual i guess and it has a light that says "shift" it used to come on right before the car shifted then after it would shift it would go off then come on right before it shifts again & so on.. also did it for downshifting. i still cant figure out whats wrong with this damn thing. can anyone help?

 

I had sorta the same problem. Check your timing and see where its at.

 

how do i go about doing that?

 

i searched how to do it & found it, i turned it only a tiny bit in both directions to feel the diffrence in both. i dont have a timing light so i wanted to see if i could feel any diffrence with my problem & it dosent seem to help how it shifts. should i still go buy a timing light & do it the right way?

 

Is it not down shifting(ie: auto trans)?? Cause your could reset your kick down wire. Or does it sound like its backfiring any when you try to accelerate? You might want to invest in a timing light I check mine every so often and it will go slightly off.

 

it dosent sound like it backfires. it feels fine until right after it shifts into 2nd, then it bucks & the gas pedal becomes less responsive, & it does the same right after it shifts into 3rd, but once im in 3rd i dont feel it anymore, until i turn or slow down, if i turn and hit the pedal at the same time the car kind of boggs & sounds like the rpms dropped. (my tach dosent work so i cant say exactly) how can i reset the kickdown cable & where is it?

 

oh, and i Will be buying a timing light as soon as i get paid.

 

As long as you think the engine is fine it could be transmission related. Ive never adjusted the kick down cable before but here is what I found when I did a couple of searches. Could be relevant to you?

https://www.thirdgen.org/forums/tran...-question.html

Maybe somethings sticking and it wants to downshift and the computer is compensating for what its suppose to do and thats why its bogging? Just an idea.

 

thanks that had info i didnt know.
however, i dont think its sticking, because it shifts into the gear but if i accelerate normally, right after it shifts into gear it has its problem, now, if i compensate with the pedal (i.e right after it shifts i push harder on the gas so it dosent have time to buck) , you cant really feel it.

 

honestly im not 100% sure its the tranny, it could be some fuel issue or something, i donk know. im just assuming its a tranny related issue because it feels like it to me...

 

You may be right. Get a timing light and see what it says. Go from there.

 

Two things - first, check the SES code. It's there for a reason, and it's easy to check, so why waste time chasing what it *might* be when you can find out what it *is*?

Second, remember your engine needs 3 things to run - air, fuel, and spark. If you're bogging down, it's because you're not getting enough of at least one of them.

It could be one of a million things, but rule out the simple, cheap things first. (and that's experience and two months off the road because of a simple problem talking. )

 

the thing is, now, its not throwing a code anymore.. & im sorry, my choice of words were misleading. its not a bogg like one from a vac leak or fuel problem, im not exactly sure how to explain it. but im sure that the bucking issue has to do with it kind of bogging. i was thinking it may be my tranny mount cus i stumbled across a thread where someone had a similar problem & it ended up being the tranny mount. i jacked my car up earlier and the mount that i can see looks completely shot. the rubber is all cracked & sticking out. do you think this may be my issue? its getting changed weather it is or not im just hoping it is whats causing it to buck when shifting. i plan on getting a polyurethane one to replace the crappy rubber one. might as well do it right.

 

How in the heck a tranny mount could cause bogging and what not beats me.

I'd go with dirty fuel system, sounds like symptoms of rotary/I4 turbo volvo engines when the fuel sock/lines get dirty. I don't see how chevy's would be any different

Have you hooked up a fuel pressure gauge?

 

like i said, im having a hard time putting it into the right words.
but no i havent checked the fuel pressure. i should be doing that tomorrow or friday. & i previously stated my fuel lines & filter are new, i havent checked the injectors yet so ill do that tomorrow

 

i should also add, its not missing, & it idles just fine, if you revv it, it sounds fine. it only has a problem right After it shifts.

 

could be torque converter not unlocking.

 

how would i be able to check if its staying locked?
also i got up under my car again today to look at that tranny mount again, & i realized there is a small tranny fluid leak coming from the front of the drive shaft where it meets the tranny. i was thinking maybe since my mount is shot, my tranny is shaking when it gets into gear (thats what it feels like) & its messing up the rear seal & causing that little leak..? im really hoping this dosent turn out to be something that i cant fix myself

 

Drive over 45 mph (IIRC) and lightly hold the break down, the engine should rev a few 100 RPM higher. This would tell us that the lockup solenoid is indeed unlocking the T/C. As far as how to check if its unlocking when you floor it, I would be using a scanner (or ALDL cable + laptop) and checking it that way.

 

so i was on the highway, doing about 65 & i figured id try that little test, so i pressed the brakes slightly and it did exactly what you said, it revved a few 100 rpms, my tach dosent work so i cant say exactly how much, but it did rev. is this a good sighn?

 

Sounds like the TC is unlocking just fine. It would be nice to see a datalog showing that the ECU is indeed commanding it to unlock when you floor it. But I would think it'd be alright.

 

cHEVy hEAVy, can use the shift light. On TBI cars the TCC and shift light use the same wire. So whenever the shift light is on the ECM is commanding the TCC to lock up.

RBob.

 

So, since my Shift light stays on, that means its staying locked?
thanks for all the help everyone
Kyle.

 

Yes. Are you saying that the shift light is always on? Or on at the proper times when the TCC should be locking up?

If always on a quad driver may be fried in the ECM. Or the TCC wire from the ECM to the trans is grounded someplace.

RBob.

 

when i first put this gauge cluster in, the shift light would come on an the proper times, but as soon as this problem started, i noticed that it stays on.

 

Then you have ID'd the problem. Now need to find out why. I would start by dropping the ECM and pulling the cover off. Look for a fried/damaged chip, usually stinks of burnt electronics.

The two q-drivers are located close to the harness connectors. If you want/can, snap an pic and post it. They are 16 pin DIP chips.

If a chip is fried, do not just replace the ECM. Need to find out which device is shorted out first.

If the ECM is OK, then need to look at the wiring between it, the ALDL connector, and the transmission.

RBob.

 

Oh I'll definately take pictures & post them. I have a few questions, where exactly is my ECM located? (I've never had to mess with it before)

Also, should I take those chips out too?

& I also figured I'd add, about two and a half months ago my air filter base, shorted out my coil, and it fried all the fusable links that meet at the starter, I think it was 3 fusable links. could this have also fried something in the ECM? It drove great for a month & a half after and then my new problem surfaced.

One more, (sorry) could the ECM or chip being fried be whats telling my TCC to stay locked?

I apologize for all the questions, I've never had a problem with these things before and I want to understand, so down the road, I'll know this if I need to help someone, or myself.

Thanks Again, Kyle.

 

bump

 

ECM is under the passenger side of the dash. The two q-drivers are soldered in. If one is damaged and hasn't burnt through the PCB it can be replaced. Yes, a fried q-driver can hold the output low and enable the TCC.

RBob.