Alright, Today i just went and changed my fuel filter on my 89 TBI (gas burns) because it was hesitating with gas and i was told it may be the filter or pump. So i get in the car let it warm up for a while (10 minutes or so) and start to take off. There was no problem as i went down the street and back giving it gas and opening it up a little bit. After about 5 minutes of driving it starts to do it again but only with a lot of gas. Then after a little bit longer it doesnt take as much gas to do it. Its like it takes a while to get worse but it will eventually get there. The RPMs bounce when the hesitation happens but so does the car. When the hesitation happens it also sounds like poppin in the exhaust. It never stalls on me but i dont ever just keep giving it the gas til it does. I also have a small leak coming from my lower coolant hose but i dont think this will have anything to do with it. I think i have covered everything. If there is anything else that would help make a diagnosis then please ask. Any help would be great. Thanks in advance.

 

Do you get a service engine soon light on the dash when it acts up? Does the exhaust smell rich? If your coolant leak gets air into the system it might be affecting the coolant temp sensor. A vac leak might be the cause of your problems. Check for loose or broken vac. lines.

 

i dont get an engine light and the exhaust does smell a little rich. my temp gauge doesnt seem to be working like it is suppose to either. It takes a lot to get the temp up. Sometimes it doesnt even go up but you can tell that it wants to. There isnt a specific route for the vac lines really is there. They pretty much go all over?

 

Vac lines do go all over, but look for any that are cracked or broken or don't connect to anything. Most are flexible rubber but there are 2 hard plastic one that get brittle and break easily, they run the heater & vent control. If you vent controls don't work and it always blows out the defrost, you have problems with these lines. I think you have air in your cooling system. This keeps the coolant temp sensor from getting a correct reading and keeps it in open loop. Open loop runs rich to warm up the engine, but if it stays there once it is warmed up it will bog or hesitate when opening the throttle.

 

Check that the thermostat has not been removed. If the engine stays cold, acceleration will be flat and the system will never enter closed loop. Fuel system is designed to work with the engine at 190` or above. The 3rd gens chronic cooling fan problems have a lot of people pulling thermostats out. If it's missing install the correct temp t'stat and check the cooling fan(s)operation.

 

When was the last time you gave the car a tune-up or checked the ignition components? How many miles are on the F.I. unit? Are you sure you don't have a valve sticking? What brand of gas are you using and what's its octane rating? Is one of the brake calipers hanging up? Have you checked to make sure your coil isn't faulty? These are all plausible reasons for the problem you described. Vacuum leaks are just as plausible. Especially around the intake and F.I. unit. I hope that helps.

 

Actually what is kinda odd is that before the heat worked and now after the fact my heat doesnt work anymore. It will come out of any vent i select but i drove it from batavia to rochester (40 minutes of 65 mph driving) and it didnt heat up at all. The temp gauge never even went up but i am pretty sure that it works. I think that everything is original but im not sure. It has 104000 original miles on it. I tried putting good gas in it last time i filled it up but it doesnt seem to make any difference what kind of gas i use. Im gonna check the t-stat tomorrow and make sure its still there. Im going to make sure and check the vac lines too. I am hoping that it is something easy and not difficult. Everyone probably does.

 

Well, it sounds like you're on the right track. If the t-stat is there, you might want to check it for proper operation. It might be sticking. If the t-stat is working properly, there's a heat riser valve connected to your heater hoses that would cause the same problem.

 

Well i figured out today i am pretty sure i have a bad coil. Not to mention the wire from the coil to dizzy was frayed and had been repaired before. I still do think there is a problem with the heating and cooling system too though. I am still going to replace the t-stat and have to check some lines. A new coil isnt going to the fix the heat and it would be nice if that worked too. Ill def stay updated and should have new parts and installed in the next few days. Hopefully this cures the problem.

 

Could be a bad plug too. Mine ran like crap sometimes and sometimes great.... turned out 1 plug was covered in oil. and low pressure

 

Yeah im going to be checking the wires and what not while im changing these few things. Im probably going to be changing the wires and plugs etc in the spring anyways. It always good to have a tune up.

 

Glad my earlier ideas helped. Don't forget to check the heater bypass valve connected to the heater hoses in the engine compartment. Here's hoping you get are fixed.

 

hopefully we will find out tomorrow because i will be changing it then. I have the new coil and t-stat. Hopefully all goes well.

 

How about a cat???

I never thought it would be but its worth checking it out!

 

I have no idea if the cat could cause this problem or not. It would be interesting to know though.

 

You seem to have the symptoms of clogged catalytic converter.


Have a shop check the exhaust system backpressure with the engine at normal operating temp.
OR
If you have the tools you or a friend can check the pressure with a fuel pressure gage. You can check at the A.I.R. pipe or the Oxygen Sensor bung.

1. The pressure should not exceed 1.25 psi at idle (warm engine)
2. The pressure should not exceed 3 psi at 2000 rpms
3. check the pipe and muffler for collapse or failure. I no obvious reason for backpressure is evident, the catalytic converter is suspected to be restricted.

 

well today didnt go as well as planned. I went to replace the t-stat first and right off the bat one of the bolts broke. Yeah what are odds. Second i wanted to replace the lower radiator hose because it looked to be leaking like i said but i think the actual leak is coming from the pump. I did also change the ignition coil and it sounded like it started up better. I got this weird high pitch whine though after i turned the car off just for a second though. Does anyone know the best way to get the bolt out and does anyone know what that whine could be? Now i guess i also get to replace the water pump. Is there anything i should look out for when doing that. Thanks for help.

 

If you still have some bolt left to get a pair of vise-grips on, lock on to the bolt and try to turn it after spraying the bolt with WD-40 or some other penatrent. Let the penatrent soak in for at least 20 minutes. If you can't get on the bolt with vise-grips, you're gonna need a bolt extractor and a drill.
The high pitched whine could be from the belt if any anti-freeze got on it. As for changing the water pump, it's pretty standard, but there is one or two bolts that you might need a swivel for. It'll take around an hour or so to change it, depending on your mechanical know how.

 

im pretty sure im gonna need a bolt extractor because it is broke almost flush. Second time i have done this. Not on this engine but my last. Im alright with my hands so changing the pump shouldnt be that bad. I just wanted to know if there was anything tricky to worry about. With my luck though who knows what will happen. How exatcly does the bolt extractor setup work. Do i drill a small center hole and follow with a different bit.

 

One trick you need to know it that the bolts that hold the water pump on go into the water jacket. So you should seal them with RTV or they will leak. The left hand bit should be smaller than the bolt hole, and drilling it in might back your bolt out if you have soaked good with penitrating oil. But if it does'nt you will need to use the extractor it should get a bite on the bolt and back it out as you turn the extractor in.

 

well the bolt def. isnt coming out so i think i am just gonna tap and die and hopefully that holds it. I dont think i should have to much of a problem with that. Another question i got now is that i gotta change the water pump. It wasnt the hose that was leaking. Its the back of the water pump. I know its only a few bolts but im not sure how to work the belt on and off and if i need any tools to do it. Id assume so. What are the symptoms of a bad water pump? Thanks for the help again.

 

It sounds like your leak is coming from the weep hole. You'll need a 1/2 drive ratchet or breaker bar to get the belt off. Common hand tools will get the rest off. Just manke sure you have a swivel joint to get one of the bolts off.

 

Are there symptoms of a bad water pump? How does it affect your daily driving? will it just cause your car to over heat.

 

A bad water pump will leak out the weep hole or it makes noise, kind of a squeal. I have never let it go long enough, but I think it will eventully sieze.

 

well i got the water pump changed today and did a new hole for the t-stat housing. Just have to tie up a few odds and ends and hopefully tomorrow she will be running again. Water pump change all in all wasnt that bad but i def spent some time putting some lube on the bolts. We shall find out what happens.

 

so i took the car out for a ride today and the problem is still there. The heat works good though so with the combination of a new pump and t-stat i got that fixed. It is still bogging down though and its looking like it more of a low rpm thing. right around 1500 - 2000 rpms. Whenever i try to give it more than just a little bit of gas it bogs down like it just wants to quit on me. Ive replaced the ignition coil, water pump, t-stat. Is there anything that gives these symptoms at low rpms. It seems to accelerate better once i get into higher rpms.

 

Here's some ideas to get you started:

1. Check all of your ignition components for wear.
2. Check the timing to make sure it's not bouncing.
3. Replace your fuel filter if you haven't already.
4. Make sure the exhaust is flowing correctly by have it checked at an exhaust shop if nothing else fixes it.

Keep us posted.

 

You did change these already? Right? If not, probably be best to do the cap & rotor at the same time.

 

i checked the wires and they all looked good. I changed that wire and the ignition coil. The exhaust seems to be flowing alright but i guess i could be wrong. Im not really sure how to test or check that without tools. Money has just been a little bit of an issue with school and not working. Hopefully in the next couple weeks ill be working and have money to do more. Im not sure on how to check the timing either. I know you have to use a light and connect it to your 1 one wire i think. But im not sure how to read it when you aim it with your balaner. Is the light just suppose to stay steady.

 

If the cat is plugged it will probably being glowing red. The timing light will create a strobe light effect on the balancer. Before doing that, it's a good idea to use some emery clothe to clean the timing tab since they get pretty rusty. There should be a tune-up decal in the engine bay that will tell you where the timing should be set. If this is a T.P.I. motor, another possible problem would be a weak diaphram in the fuel pressure regulator. Not trying to get off subject, but I figured I'd at least drop that little note. Keep us updated.

 

i got a little more that might help put a diagnosis on this problem. I went out and took the air cleaner lid off just to see if that would make any sort of difference and i thought it did until my car warmed up. It seems that when the car heats up the idle drops down a lot. It idles a little bit under 750 rpms. When it gets that low the oil pressure goes down a lot too right above the 1/4 mark. When i start my car it starts at about 1500 rpms and gradually makes its way down as the car heats up to about that. Could there be something wrong or is this a normal configuration?

 

What you're describing is about normal for these cars. Now when you say the car hesitates of the line, is it like the car starts to take off and then the nose dives for the ground, or do you just feel the car doesn't accelerate as fast as you would like?

 

it violently jerks. You could say nose to the ground. Its def not like a bad wire where its just not as smooth but you can still accelerate. It will almost die for a second and come back and hesitating like that until i let off and just give it a little little bit of gas.

 

i just checked the injectors to just to see how they sounded and they are both sounding good. Just another thing ruled out of possibilities.

 

Is this a hose for a vacuum and if not what does it do? I was playing around just to see if anything popped out at me and was wiggling wires just to see and that hose when it connects to the manifold was really loose. I tried to pull it off and it came off really easy and the underside of it was ripped and not really closed at all. Just wondering if this could of caused my problem or what kind of problem this would cause if any at all.

 

Yeah, its a vacuum hose.. It supplies vacuum to the cruise control and HVAC system.