turbo hci problem

[bzsport350]

Hi guys i am the proud of owner of yet again another HCI. It is a 1987. I had an 1986 back in the mid 90s and then upgraded to a 99 sport350(US edition) which i had done work to. Havent had a boost gauge in a while. Here is my problem. The HCI are supposed to have 9.5lbs of boost. When i floor the car the gauge only reads 7.5lbs of boost but when i lift off throttle it spikes to 10lbs. So while I am stepping on it in whatever gear, it never reaches the 9.5lb range. Is that normal? I have checked all vacuum tubes to see if any ripped or disconnected but everything seems fine. Can it be a wastegate problem or a turbo problem? Thanks guys

[trackmagic]

You might see if the recirculating valve (blow off valve) is seating properly.

Best

Jeff

[bzsport350]

I dont think my car has a blow off valve. Its bosch injection. If it does where is it?

[red vtec]

Could it be a gasket? check the one on the plenum chamber.

[bzsport350]

OK started fiddling around this morning. Car as of late developed a ticking noise almost like a lifter. It turns out to be the hose that comes out of vacuum pump to the rear of the car. One does that mean I have a vacuum leak somewhere or two is the pump going bad? Brakes are kind of hard. Lastly can that effect boost. All vacuums on engine are connected

[trackmagic]

That hose is the air inlet for the vacuum pump, it does make some noise.

The valve I was referring to should be located near the airbox. Look for a round cylinder with a vacuum hose coming off the top. It will also have a hose attached to it. You can pull it off to check it is functioning.

Best,

Jeff

Just a side note there Billy, if you haven't done so you might want to consider becoming a member of this site so you can get access to the extremely valuable parts and service guide. It would be very worthwhile for what you are tackling.

You will thank yourself for doing so.

Best,

Jeff

[Mesprit87]

I should be able to help you with boost values but this being the first summer I really drive the car, I just enjoyed it and didn't really mind what kind of boost values it would put out!!

Sorry,

Luc

[stevem]

OK started fiddling around this morning. Car as of late developed a ticking noise almost like a lifter. It turns out to be the hose that comes out of vacuum pump to the rear of the car. One does that mean I have a vacuum leak somewhere or two is the pump going bad? Brakes are kind of hard. Lastly can that effect boost. All vacuums on engine are connected

loud ticking noise can be heard if there is a vac leak. Do all your heater controls work OK - if not the leak could be under the dash somwhere as the vacuum is used there, or where the kplastic vac pipe is 'T'd off - on MY88 it's over the offside rear wheel arch, not sure about the G car

Edited December 8, 2011 by stevem