jutammel

Hi there, I have noticed that my car has a weird problem when accelerating. When I do partial throttle acceleration from dead stop, it goes like a rocket but if I smash the pedal all the way it starts to accelerate but kinda bogs down for a few seconds ?! I have noticed that bogging happens at WOT acceleration when my car changes to 2nd gear. I usually accelerate shifter in D. I have also noticed that if I do a steady acceleration (not WOT) I have to push the pedal WAY more when it shiftes to 2nd gear to keep the car accelerating at increasing curve.

I don't understand becouse everything should be in top condition. All fluids and filters changed this summer. Ignition upgraded to Davis coil kit, Taylor wires and Dynamod ignition module. TPS sensot set to 0,65v and fuel pressure at 45psi at idle vacuum line disconnected. Car has also all minor/free mods, no pre-cats, high flow main cat and magnaflow exhaust and ported plenum. My evaporative emission system is not currently connected, could that cause such a problems?

Any ideas please

mackeyred96

That bog could be the trans going away. If it is the next step will be that at WOT it won't **** at all and hits the rev limiter.
Now is it a bog or slow in shifting???

jutammel

That's the weird thing becouse it shifts REAL crispy. I have tightened the TV cable and 1-2 shift is really neck snapping and 2-3 has nice punch too. Transmission seems to be working like a dream but I just can't understand why it bogs when accelerating in D. Bogging happens when transmission shifts to 2nd....
Really frustrates me becouse it starts to accelerate like a rocket then bogs down for a few seconds and start going again with no problems... Bogging is not so obvious to casual passenger but you can definetely feel that it just doesn accelerate. My friend noticed it though and asked " what hell was that? Did you release the pedal..."

bogus

Sounds like the base timing is a bit off and the TV cable needs to be adjusted.

Have you ever set timing on a car? If not, it's very easy.

First the base timing. Base timing is just that - it's the base line mechanical timing setting for the engine. The computer has to start somewhere...

You need a timing light and a wrench (9/16", I think). There are special tools available, cause the bolt can be a real bitch to reach. The bolt is on the passengers side.

The wrench will loosen the set bolt that holds the distributor.

Before you do adjusting, there is a wire... a tan or brown one... somewhere near the power brake booster, against the firewall, that has a connector. Disconnect the connector. That connector will stop the computer from trying to manipulate timing. The connector can be tricky to find... and an even bigger bitch to remove... just a warning.

Attach the timing light. One lead goes to the positive and negative posts on the battery, respectively. The big thingy goes on #1 sparkplug wire.

On the crank balancer, there is a mark. That mark is sequenced, or timed, with the #1 spark plug, when it fires. That big thingy on the timing light harness is an inductive pickup, it picks up the energy of the spark and turns on the light for an instant. Aim the timing light at the mark and pull the little trigger. You will see a strobing effect that will light up the crank each time the mark goes by. On the block there is an index that you will match up with.

For an 88, I think the base timing is 6* Before Top Dead Center.

To set the timing, whilst the engine is running CAREFULLY turn the distributor so the timing mark moves up or down on the index. I think you want the 2nd valley on the index (it looks jagged). The first valley being 4 degrees, the high being 5 degrees and so on.

Next... the TV cable. This is done with the engine OFF. This cable connects the transmission to the throttle. There is a metal bracket that has the throttle cable and another cable on it. This is just before the throttle body. The other cable is the TV cable. The TV cable has this large "D" shaped thingy there, it's plastic with a metal insert. Using a largish open end wrench (18mm?), push the metal insert. Then pull the TV cable back towards the firewall. There are detents, so it might be tight. once it stops, stop pulling.

grab the throttle cam with your hand and yank it to max throttle. It might fight ya, that's fine, but it MUST go back to full throttle. Once done, the TV cable will snap back into adjustment.

I did both of these things on bastet44's 87... made such a difference!!!!

jutammel

Base timing could be it. I have forgotten to check it completely. My ignition setup is like this: AcDelco rapidfires gapped at 0.45, Davis coil kit, taylor wires and Dynamod ign.module.
I will have to check that timing to be sure.

I have however adjusted that TV cable and it is in proper adjustment so that can't be it.

jutammel

I believe I could use 8* advance in my setup?

rick lambert

Checking the timing would be my first step too. But if your timing is ok this is what another forum member found. A faulty coolant temp and oil temp sensor was the culprit. The ecm tries to correct the problem without storing the fault, therefore it corrects the problem before it reaches a fault code, and causes the delayed response time.

vinnies87

Changed my timing to 8* and set TPS to 65, reset and cleaned IAC, set base idle to 550 and made quite a difference..