[mikebw]

Yesterday morning I drove to work, went to accelerate onto the highway and got nothing- it was like the engine stopped, no power at all, but it didn't shut off, after I let down on the gas it continued to idle, I was able to get right off the highway and drive on the slower roads well enough.

Problem I would guess is something in the fuel delivery, it is intermittent and seems to get worse when it is cold outside. I can sometimes get tons of power, great acceleration, but other times it chokes and I get nothing. Has never been as bad as it was yesterday though.

I had replaced the spark plugs and distributor cap/rotor last year in an attempt to fix this same issue (which seemed to help at the time) but now it obviously is something else.

I have read up on Jim Hopkins' posts (over at the Yahoo Cressida group) about EFI and the fuel filter issue, so at this point I am thinking most likely it is a vacuum problem somehow causing the system to not provide enough pressure or fuel when it is supposed to.

Any thoughts on this? I have not dealt with fuel lines before and feel slightly out of my league on that. Almost bought a new fuel pump but then saw you need to drop the whole tank to replace it. Is it a hard job?

Also read how the fuel pump sends a constant volume of gas regardless of the throttle position, so I am thinking since it idles fine and generally accelerates fine that the fuel pump is OK, not sure how to proceed.

Any suggestions?

Thanks,
-Mike

 

[kamesama980]

1st thing to do: pull codes. go under the hood to the diagnostic connector and use a bit of wire to short pins TE1 and E1. then go inside the car and count the flashes of the check engine light. they'll be grouped into 2 digit numbers. each number will repeat 3 times before going to the next one. once you get to the end it'll repeat. I'm guessing it's not the vacuum operated regulator either since the reg without vacuum applies full fuel pressure all the time. the vacuum compensation lowers pressure when manifold vacuum is high not the other way 'round.

a related issue that might be something to think about, I've known a few guys that had trouble with crud in the tank clogging the fuel pump strainer. when yours bogs down, is it usually after you've been driving a while? if you shut the car off for a few seconds, does it run fine with full acceleration?

 

[mikebw]

So if the vacuum hoses were leaky then it shouldn't affect the maximum fuel delivery capacity of EFI system?

Generally I experience this problem on a cold engine, the more I drive the better it gets. However sometimes if the symptoms are present and I do stop somewhere and shutoff the engine, when I come back it seems better. Not sure if that is really conclusive evidence as it doesn't seem consistent.

I should note that there are a number of other small issues with the car at the moment that may possibly be part of this issue but I didn't want to complicate the original question. 1. The radiator leaks slowly from the lower hose where it clamps onto the radiator, I regularly top it off. 2. The exhaust pipe is rusted out just before the cataylitic converter. 3. The gas tank seems to leak if I fill it up more than half way. There will be a smell of gas about the car and sometimes a damp spot on the ground near the passenger side rear wheel. I don't drive the car much so I just don't fill it up more than half way and it isn't a problem.

At the moment I don't think it's worth it to fix all these side issues unless they are actually causing the acceleration issue I am experiencing now.

 

[kamesama980]

in this case they don't help but generally, list EVERY symptom and EVERY problem you know of. sometimes seemingly unrelated things will cause problems. more detail will give better and faster answers. In this case I don't think they are related though.

From what you're saying, it's definitely not a fuel supply problem (tank, lines, FPR). Like I said, pull the codes (I just put a sticky at the top of the section, lucky you you get to be the first to use it).

Does it have any correlation to humidity or air temperature? My pickup has some bad wiring and acts up whenever the humidity and temperature conspire to get condensation, the TPS and AFM common circuit goes in and out so if I go over a certain TPS% or AFM% it sputters and tries to die.


I've actually got a good tank for a MX73 but it's 6 hrs away at my moms house which is about 1000 miles from you. if you can't find anything closer and want it, I can look into shipping.

 

[katman]

My 85 started out dying with heavy acceleration, then with light acceleration, then it would only idle with no throttle. I replaced the fuel pump and wallah, problem solved. A few things to remember when changing the pump...and trust me, the labor cost is 10-15 times the cost of a OEM fuel pump, so unless you are heavily invested in the Cressida I would DIY with a $30 pump. 1) raise the car high enough to get under it and adequate room to drop the tank. 2) empty the tank (drain plug with square head plug on bottom of tank. 3) pull the power from the battery. Once you have the tank down it is as easy as a few bolts removed and taking old one out and re-attaching new one.

 

[zythr]

The pump is not on the outside of the tank?

 

[katman]

Atleast not in my 85. Its inside the tank going in through the top. Can't change it without dropping the tank. With the right tools you can do it in a few hours by yourself. Got mine on Ebay for $30. OEM. Honestly at that pricepoint I wouldn't waste a whole lot of time investigating multiple sources of the problem. The majority of the time it will be the pump. I have gone through 2 in 5 years. Bad gas? Who knows, but change a couple out and you'll be a pro at it.

 

[Cusker]

It does sound like it could very well be a fuel pump issue. I had one fail in my '89 Dodge Colt Turbo. My symptoms were not being able to give it any more than an 1/8 throttle or it would fall on its face and the pump got real loud towards then end.

Typically swapping out an in-tank pump isn't difficult, just a little awkward when dropping the tank. Be prepared that you may want to have the tank boiled out at a radiator shop while you have it out (assuming Cressida tanks are metal). The tank in my Colt was pretty rusty inside. After having it cleaned it looked great inside and I knew I wasn't going to be pumping rusty gas through my nice new pump.

 

[Tech1984]

Mike, this might be worth a try first. Carefully cut open the top of the air flow meter and clean it out with some contact cleaner. Then air dry.
Any dirt on the potentiometer sends it out of whack.
I worked on these cars new and fixed many for this symptom like yours.

 

[kamesama980]

$30 pump.... you get what you pay for.

If you've changed the pump more than once, something else is causing the pump to go bad, fix that or you'll continue replacing them. or it's your source of fuel pumps.

Typically the pot in the AFM is damaged not dirty unless someone has had it open before. it's sealed for that very reason. same goes for the TPS.