dattson510 Posted June 15, 2010 Report Share Posted June 15, 2010 Hey Guys,It's been a while since I've owned a StarQuest but I bought an 87 yesterday. I just couldn't stay away.... Anyway, I drive it about two blocks and stop to get some celebratory lunch. When I get back in I crank it and it fires for a second then dies. I knew it was very low on gas so i figured I had ran out. picked up the gas can and put two gallons in it. Cranked it and still wouldn't start. After a while I popped the hood, turned the key to on and there is no fuel pressure showing on the in line gauge. Also can't here the pump trying to prime. Could it be my bad luck and the knock box went out? If the KB is out will the pump still turn on?Any thoughts?I'm having it towed to the house in a bit so I can start working on it. Thanks Link to comment Share on other sites More sharing options...
vbrad511 Posted June 15, 2010 Report Share Posted June 15, 2010 does the tach jump when you're cranking it? if not...knock box most likely Link to comment Share on other sites More sharing options...
dattson510 Posted June 17, 2010 Author Report Share Posted June 17, 2010 i went back to get the car and when i opened the hood I noticed that the knock box wasn't grounded. Threw a bolt in there tuned the key and instantly had fuel pressure. Got a jump and was off. The problem is still there. Sometimes it fires right up and runs great. Other times it just cranks. I check under the hood and the fuel pressure is 0. The tach does move when I crank it. Fuel pump going bad? Do I have to drop the tank to replace?Thanks Link to comment Share on other sites More sharing options...
StarquestRescue Posted June 17, 2010 Report Share Posted June 17, 2010 Sound like a bad knock box, also called an igniter. The 87 and older were known for this. Some repace it with an 88-89 unit. This requires changing the igniter plug. Link to comment Share on other sites More sharing options...
h3r3tic Posted June 17, 2010 Report Share Posted June 17, 2010 yes you gotta drop the tank. I think I have a simliar problem. My fuel pump is brand new so its not that. Im gonna replace my 87 kb with the 89 I got Ill let you know if it fixes it. Link to comment Share on other sites More sharing options...
Shelby Posted June 17, 2010 Report Share Posted June 17, 2010 a missing ground wire on any igniter box can cause spark to jump back to the ecu , causeing all sorts of hard to find problems includeing but not limit''d to fail'd igniters and bad ecu's Link to comment Share on other sites More sharing options...
dattson510 Posted June 17, 2010 Author Report Share Posted June 17, 2010 Is there a way to test the ECU to see if it's functioning properly? Link to comment Share on other sites More sharing options...
Indiana Posted June 17, 2010 Report Share Posted June 17, 2010 There are things you need to check before you go pulling out fuel tanks or thinking your pump is bad. There's a test port for the pump behind the air filter can and in front of the cruise actuator on the passenger fender apron, its a single terminal with a cap on it you just put a jumper from that to the positive battery post and the pump should run. If that pump has a bad or removed damper/check valve no you won't retain fuel pressure but for a few seconds or minutes depending on the pump. If you don't hear the pump maybe it just died because its supposed to run with that test port whether the key is on or not. If you hear the pump but get no pressure you may have completely ran the tank out and the line is empty so you are having the pump try to draw fuel up the hose from the tank and old pump can have trouble doing this you may just have to remove the inlet hose to the pump and prime it. You are not supposed to run this car out of fuel, the fuel also cools the pump. Under the false hatch floor on the drivers side is a oval tin panel about 4"x9" or so and under there you'll see the pump and the connection and the inlet hose. Your spark plugs if fouled won't fire or an injector could be stuck but first find out if the pump is working. Link to comment Share on other sites More sharing options...
v1xiii Posted June 17, 2010 Report Share Posted June 17, 2010 Indiana, I'm going to have my fuel pump replaced soon due to a similar issue and have heard that I don't need to re-use the damper/check valve and can just run a new line directly from the pump to the hard line. Is this correct? The pump is a Bosch 69400. Link to comment Share on other sites More sharing options...
Indiana Posted June 17, 2010 Report Share Posted June 17, 2010 If you want its your car you have to find an adapter to fit the stock hard line. If the damper is good then use it why would you not? The fuel pressure is retained in the stock high pressure line from the pump on the other side of that valve all the way to the fuel pressure regulator in the throttlebody. You hit the key and all the pump has to do is build pressure for that tiny bit of fuel that's already in the pump then the damper opens at 64-85psi. That means your injectors will always have full pressure the very first time they fire, if they have low pressure that means they will dispense way too much fuel at the beginning making for harder starting. Why would people want to remove it? If its rotten alright but that's not always the case. Link to comment Share on other sites More sharing options...
h3r3tic Posted June 17, 2010 Report Share Posted June 17, 2010 (edited) How do you put a dampener on an after market pump? like external walbro? Im assuming the dampener was the lil diaphram looking thing where the banjo bolt connected is that correct or is it the lil box that was wired in? Anyways when I removed the pump That thing on top of the banjo bolt was rusted through and the spring just felt out. So if that was it I assume it was not working correctly, can be why I had a hard time starting before and after the pump change? oh by the I put the newer knock box in and it didnt change a thing. Edited June 17, 2010 by h3r3tic Link to comment Share on other sites More sharing options...
Indiana Posted June 17, 2010 Report Share Posted June 17, 2010 Sounds like yours was rotted. http://www.b2600turbo.com/images/reg1b.jpg Link to comment Share on other sites More sharing options...
Indiana Posted June 17, 2010 Report Share Posted June 17, 2010 (edited) That picture is misleading, there never was a check valve as shown in the picture, the part that sealed was the plate in the damper that covered the pump outlet. Hondas used the same thread part because there's an AN adapter available. I've never seen the Honda damper though. There is also an adapter for pumps without a damper from Russell. http://www.b2600turbo.com/images/IM003725.JPG Edited June 17, 2010 by Indiana Link to comment Share on other sites More sharing options...
h3r3tic Posted June 17, 2010 Report Share Posted June 17, 2010 well iis that possibly the problem? only problem I cant fix is the misfire. If I hold steady ate 2k or 3k it like spits. Link to comment Share on other sites More sharing options...
dattson510 Posted June 17, 2010 Author Report Share Posted June 17, 2010 The tank has never been run dry. I thought that it might have before I noticed the missing ground on the KB. I know if it's going to start when I see the in line fuel pressure gauge reading 40psi. It is either 40 or 0 no in between.When i have the pressure it starts right up and I've driven for about 25 min or so playing with the throttle to see if there is any lag or if it will quit. No problems. It runs strong and smooth. To me it seems like the pump is OK, but sometimes it's not getting the signal to turn on. If the ECU has been F'd up or the relay, is there a way to test for proper functions.Did some research and a new KB is $300-500? really? Can the KB be replaced with an MSD or something less expensive? Link to comment Share on other sites More sharing options...
h3r3tic Posted June 18, 2010 Report Share Posted June 18, 2010 Ive hooked up a gm hei7 module with a megasquirt before with the stock coil , distributor. I am not sure if you can do this with the stock ecu still though. Link to comment Share on other sites More sharing options...
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