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Problem with low RPMs

2K views 15 replies 6 participants last post by  nickCR 
#1 ·
Hello Forum,

This would be my first post here for help. I live in Costa Rica and the mechanics here are not the best, in fact my taking an educated guess would be better then to give them the car.

I am hoping that you guys can help me find a solution to the problem/s i'm having.

1. I have seen many people with problems with their IDLE, in my case I don't have a problem with the IDLE i have a problem when I press the gas peddle, between 1,000 - 2,000 RPM it really is rough, feels like it's missing but at the same time choking for gas. I took the car to a mechanic, we bleed the top of the Fuel Distributor and cleaned all the injectors (the fuel that came out of the Distributor was redish - rusty). Well that didn't help much. We then took the car to Bosch, there they hooked it up to the machine and made some adjustments to the distributor and the problem stopped. Well 3 days later it has returned once again (this was 2 days ago). This morning when I started the car it was fine then about 5 min into the drive it started the same problem again. So it seems like the problem comes and goes. Any ideas? Since I have had the car, I bought new cap, rotor, wires, plugs, Air filter so it's not that (within the last 5,000 K I did these changes)

2. There is a strange squeaking sound in the back left side of the car. When the suspension compresses or releases you can hear the squeak. It's like the spring is squeaky but this happened after the mechanic tighted some other problem.

Thanks in advance for your help!

Nick
 
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#3 ·
I had this same exact problem myself. They started with new wires, rotor, plugs, cap, etc for me, too. Didn't fix my problem either.

They replaced an ignition coil. Didn't fix it. They replaced my injectors, and that definitely helped for a while. Then I had the head gasket replaced and a valve job done and the problem came back. Got a new O2 sensor, a bunch of other crap, and the problem persisted. Then finally, he said it was my fuel distributor. Problem was, he said the part is $2,200 brand new. He was able to find a guy in california who rebuilds them- got it for $800 with labor... he gave me a break cuz of all the stuff going wrong with my car. The fuel distributor definitely helped, but I still have a hint of the same problem. Apparently the dude who rebuilds these things said they'd had problems with them in the past, but they have revamped their manufacturing processes and have it straightened out. The conclusion is either (1) I got a bad rebuilt fuel distributor, or (2) It wasn't the fuel distributor in the first place. I have been too busy and scared to take this car in again, afterall, I've dumped like $7,000 having it fixed over the last 18 months!

Well, I hope that helps a little. It sounds like they're looking in reasonable places...
 
#4 ·
BigPete,

I really appreciate your answer. I think we are having the exact same problem and I bet i'm gonna figure it out tomorrow. I'm taking my car to Bosch and they are going to put it on the computer and i'm gonna pay them an arm & a leg to find this retarded problem. But I bet in the end it will be much cheaper then ordering the part. Also just for your info after searching the net there are many places offering the Fuel Distributors (rebuilt) for $500 or less. Here is Costa Rica I can get them at $900 locally that is...

Again appreciate the response i'll post the updates here.

Nick
 
#5 ·
Well if they don't find the problem tomorrow we are gonna take my car to the shop and put a fuel distributor that is working and see if it does the same thing.

I also saw on here posted somewhere if you pull the electrical plug out of the distributor and continues to do the same things you know it's the fuel distributor. What about the Fuel Filter? Did you replace that? I haven't I gonna find out if it's that, did you have a rusty color gas when the mechanic bleed the fuel distributor?
 
#6 ·
Hmm,

If it is hesitating just above idle, and your fuel color is rusty, then I'd suspect the filter and/or pump first.

Had my filter changed, but has to redo it, after about a year, as the filter got clogged again. My mechanic recommended that the gas tank be flushed as well. They didn't need to touch the engine side.

In areas of high humidity, because of the water contamination in the fuel from the station, the gas tank does seem to get deposits more often, and yours being an '88 in Costa Rica, it seems about time.

(The pump is IIRC under the left side of the car)

Cheers,
WS
 
#7 ·
Ok guys here is the latest.

I went back to the mechanic instead of taking it to Bosch and they changed the distributor over from another car and it had the same problem. So we knew it wasn't that. However my father and I decided to play mechanics in the meantime and we took the distributor off and cleaned it out and well we didn't set the pin on the bottom correctly so it didn't work lol we figured it out but I had to buy a new one in the mean time and I burnt out my starter beacuse it was putting to much gas in.

Then they do a leak down test and find that one of the valves in the head was not holding any liquids at all. So what do we do but send it to be completely redone. After some snivling and whinning, I got him to do all the work including new valve guides and a complete head job for $1500 including the starter, and distributor.

So I left and it worked perfect for about 2 hrs. Then it started doing the same thing again but on a much smaller scale then before. So I was not impressed especially after spending all this money. We have determined that the 3rd cylinder from the front is the one causing the problem. We can pull the wires off all the other ones and see significant change in the engine idle. When we pull it off the 3rd one it doesn't change much at all.

I have pretty much run out of ideas if anyone has any clue what it could be please let me know. I have pretty much replaced everything that is mechanical. We have replaced all the plugs, cables, distributor cap & rotor.
 
#8 ·
Saturday Morning Adventure

Hi All,

Well this morning I took my car to another mechanic. I was feeling a little un-comfortable with the one I had especially after $2000 all together with the same problem. So we looked over the car and found that un-pluging the black box on the fuel distributor did nothing. So this told us that the problem was bofore the fuel distributor. We did some test on the O2 sensor and found that it had no power. So we look under the passenger seat and viola guess what these rejects from the first shop had un-pluged the thing. So we plugged it back in and the car ran a little better. However there was still a problem with the mis-fires and low RPM sputters.

After all that we decided to take the car to Bosch to put it up on the machine for Tuesday morning. I hope that we will find out what the problem is. Worst case scenario is that we replace the injectors which are very old. At $100 a pop it's gonna be $600 but $2600 and I guess I pretty much have a new car. Now I guess it should have only been $600 from the start but anyway what can I say. Dumb mechanics it was :(

I'll let you all know on Tuesday how things turn out.

Nick
 
#11 ·
Hi Guys,

I have tried the Fuel Cleaner and the fuel filter was just changed.

Lets make a list:

1. Spark plugs (everytime they are drenched 3 sets)
2. Spark plug wires (bosch new)
3. Distributor Cap (bosch new)
4. Rotor (new)
5. Fuel Distributor (used)
6. Fuel Filter (new)
7. Full Head Work (valve guides and seals) (new parts / rebuilt head)

What else can I do except change the injectors. That is what we are going to do tomorrow check them all on the machine at Bosch. If they are faulty then we know where the problem lies.

Nick
 
#12 ·
Thought i'd give you all an update and a funny story. So I took my car finally to Bosch (dealership) and they dig a head to toe on the engine. They ran through every electrical connection, sensor and whatever else they could to make sure they found the right problem. The guy called today and said come take it for a spin, we want you to let us know if there is anything that you feel wrong with it still. I took it and got back with a big smile on my face. It was most definitely fixed. Well I still don't know the price for these repairs. I'm expecting $800 due to all the work and parts (6 injectors). I got the bill and it was $200 all parts and labour final. Apparently the injectors are only $25 each and the labour was only $50. Mind you my father has been going there a really long time and they have always treated him extremely well. So anyway the funny part is a I spent $2000 to fix a $200 problem. Wooopi but whatever I know my car should run for another 10 years because they told me the fuel distributor I bought is 90% good (comprared to 100% new) which they told me I hit the lottery being that it's almost new.

So anyway just wanted to let you all know what happened here.

Nick
 
#13 ·
just a question, where your spark plugs coated in oil, because this happened to me and it turns out the engine needs to be replaced. i can get one for 600 so i will, but this problem seemed to go away for a week then would come back as oil would build up and fail to burn off.
 
#14 ·
Well 5 of the 6 plugs were white (meaning clean burning). 1 of the plugs was black from carbon. So this simply told us that there was a problem with one cylinder. What happened is that everytime they pulled the injector out and cleaned it, it would run fine until some dirt would build up in it.

Either way it's fixed for sure now. I have a little funny start problem. Doesn't start right up like it did before but I think this is because of the valve, however my windshield wiper works like it's on steriods now I think it was one of the connections they cleaned.

In your case it sounds like your rings need to be replaced. This doesn't mean you need a new engine as that can be very expensive. You need to rebuild the bottom of the engine and replace everything that needs to be replaced while down there. (CrackShaft bearings, connecting rods, rings) if you do those things then you will have an engine that will last for another 10 years.
 
#15 ·
no, actually, it is leaking from the top, and while it can be fixed im looking into what that would cost versus picking up an engine for $600. especially considering that my current engine has made it 240,000 miles. so to get an engine with only 130k on it, and a fuel distributer descirbed as "practically new" I have to think about what makes more sense.
 
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