no acceleration after warm up

[kytarheel71]

Well i finally got to working on my 87 si automatic again. New problem now. I changed the alt. and new power steering pump because it was leaking. Also replaced the cooling semp sensor like suggested.. Also started replacing some vaccuum lines. after it runs and gets hot or warmed up about 10 min, it starts acting like it's gonna stall when you give it the gas. Has no acceleration at all. I tried another used EGR valve and got the same result. I ran a little seafoam through the intake to clean those out a little bit. When it is parked and just idling it sounds perfect, right around 950-1000rpms. If you give it gas while in park it is fine also. Just when you are under driving conditions.Plugs and wires were also recently replaced.

[spiffyguido]

That's an intersting problem. I'm going to get you to describe it better, but in the meantime here are a few things that I can point you to.

Since the problem happens when you are in drive, your issue is likely related to one of the systems that is engine-load dependent. Off the top of my head these include the TPS, EACV and a few vaccuum lines. I've seen a TPS go bad, and had my own EACV go bad, so let me know if either of these sound familiar.

For the TPS, the car that had the problem would seem fine when idling, but as soon as you wanted to go somewhere, it would accelerate to a certain RPM (in this case, about 2500rpm) and then the engine would fall flat on its face and sputter back down to idle revs before you could get the car to accelerate again. We traced the problem back to the TPS sensor, replaced it, and all worked fine. The TPS sensor on your car is likely riveted to the throttle body, so if you can get another throttle body from a wrecker and you think this is your problem, it's an easy fix.

For the EACV, my car would drive just fine, but at certain engine loads the engine would 'bog' badly. It made the car very hard to drive. Wide open throttle was fine, idle was fine, but mid throttle was horrendously bad. Engine would bog, power would go away, and it was very hard to drive. I'm not even sure that your car has an EACV system, as these may not have been introduced until later. They are usually cylindrical in shape and mounted horizontally to the (front usually) intake plenum.

Lastly, this could be related in some way to your tranny. I'm pretty unfamiliar with auto transmissions, but I do know that the auto transmission control unit does talk to the engine ECU and tell is about what gear is selected and what the load is, etc. This may be playing to the situation. We should probably find out if there is a way to read the tranny fault codes on a 2nd gen car. I know there is on the 3rd gens, but unsure about 2nd gen.

[kytarheel71]

This is just a shot in the dark but i am going to check the plugs. I have had 2 people tell me today to check and see if the plugs are fouling out. One guy said that is exactly what his old integra used to do. It would run fine for 10-15 minutes and then would bog down something awful if he tried to accelerate. If he babied the accelerator he could slowly go faster but he really had to do it slow. If he pressed to hard it would bog down and just about die. That is exactly what mine is doing. If i baby it i can get back home. I just have to go extrememly easy on the throttle and i mean easy. Also when you first start it , it shudders something awful, i mean the whole engine shakes like you wouldnt believe. This last for maybe 2-3 seconds, then goes away. Another friend told me this is a symptom his old car would do because the plugs would go bad for some other reason i cant remember but he said the shuttering was because of the plugs not being gapped right.What do you think.Somewhere in this is i hope a better description of what the car is doing.
I mean i changed some vacuum hoses but i did these one at a time(one off -one on). So i know i didnt mix any up. I have also heard about air in the cooling system. We dained the cooloing sysytem because it was nasty, and i thought we bled the system OK. Maybe i didnt though. I know there could be many diff reasons why but i dont want to keep buying parts for it that i may not need at this time.
If this was a motorcycle i could figure it out but i am still a novice at the car thing, basics and a little more i can handle, but i am starting to get stumped.

[spiffyguido]

It is within the realm of possibility that bad plugs could cause your problem. At any rate, if there is any doubt about their condition, they are worth replacing regardless. Keep in mind that part of the spark system is the distributor, so you may also want to check that your distributor cap is in good condition as this can affect spark quality.

PreludeDriver.com has produced a video dealing with spark plug replacement. The video is for a 3rd gen prelude, but the procedure is essentially the same. You can view it using the link below.

http://www.youtube.com/watch?v=ML1IaeScmAE

[kytarheel71]

Well i checked the plugs and they appeared to be OK but i'm gonna change them anyway for good measure.

While i was checking stuff in that area i noticed that the distributer cap was kinda loose. come to discover that the bottom bolt (only saw 2) was not threaded all the way in. Tried to tighten it up but found it was broke, or the wrong one. Wouldnt tighten all the way up to body. Could this possibly be the problem. Will probably check on getting a new one tomorrow, doubt they have one in stock though.

[spiffyguido]

Make sure that distributor cap is properly tightened, then reset your timing. That might be the root of all your troubles.

[kytarheel71]

Reset the Timing? Sorry but tell me how , I probably dont have the tools. Putting a new dist cap on now and it is going in the shop on Friday to get a new timing belt and water pump. Was never able to get the crank bolt out so i am gonna bite the bullet and have a shop do it for me.


Okay looked up setting the timing, dont have a timing light, so that will be up to the shop. Question what is the firing order. I looked at current setup and it just doesnt make any sense. Facing the car in front from left to right what is the firing order. Am looking in the shop manual but cant find it.

[kytarheel71]

Ok i had to take off the whole distributer. Bolt was broke off in the dist. body and had to drill and retap it. Cant get the damn thing back in now. I see u have to line up the notch but is there a trick to it , dont want to break it. T- storm rolling through now so i had to stop, no garage, perfect timing#*@#*#!.

[spiffyguido]

Firing order is 1,3,4,2. It's usually indicated on the outputs on the distributor cap so that you don't wire things up incorrectly. The number 1 cylinder is on the timing belt side of the engine (crank pulley side), so if you're standing in front of your car, looking at your engine, the number 1 cylinder is on the right.

Timing is easy to do using the timing mark on the flywheel. Just hook up the timing light to the spark plug wire and adjust the distributor cap by twisting it until the mark lines up with the flash from the timing light.

[kytarheel71]

Got all that done except timing, off to the shop tomorrow

[Crash_Control]

Have you ever checked the fuel pressure ?
I have seen it where a fuel pump works great when cold ,but when warm it can't put out enough fuel to run the car properly.

[kytarheel71]

Thats the next thing i will be checking. Even had the cat coverter removed because you could smell that rotten egg smell of a clogged converter, new dist cap also.
Still does the same thing. We tested the injectors and they showed good. Dont have a fuel pressure gauge yet. We are also gonna put a new fuel filter on next week. When we first got the car the gas tank had crap in it, but we dropped it and cleaned it out.

[spiffyguido]

Fuel filter and checking the fuel system as mentioned by Crash are great ideas. Let us know how things work out.

[kytarheel71]

Well i checked the fuel pressure and it read between 34 and 35. Shop manual says 36-41. does that little bit a difference count. i also checked the fuel pressure regulator and it checked out OK. I am gonna replace the fuel filter anyways and then check the readings and i hope it reads higher. That will at least tell me it's the filter. Have to order one cause no one around has one in stock.

[kytarheel71]

Put a new fuel filter on and getting the same psi 34-35, pressure regulator checks out OK. Injectors check out OK, have not test drove it yet but i suspect it will do the same thing. Any ideas guys?????